Solve for h
h = \frac{3}{2} = 1\frac{1}{2} = 1.5
h=4
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2h^{2}-11h+12=0
Divide both sides by 4.
a+b=-11 ab=2\times 12=24
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 2h^{2}+ah+bh+12. To find a and b, set up a system to be solved.
-1,-24 -2,-12 -3,-8 -4,-6
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 24.
-1-24=-25 -2-12=-14 -3-8=-11 -4-6=-10
Calculate the sum for each pair.
a=-8 b=-3
The solution is the pair that gives sum -11.
\left(2h^{2}-8h\right)+\left(-3h+12\right)
Rewrite 2h^{2}-11h+12 as \left(2h^{2}-8h\right)+\left(-3h+12\right).
2h\left(h-4\right)-3\left(h-4\right)
Factor out 2h in the first and -3 in the second group.
\left(h-4\right)\left(2h-3\right)
Factor out common term h-4 by using distributive property.
h=4 h=\frac{3}{2}
To find equation solutions, solve h-4=0 and 2h-3=0.
8h^{2}-44h+48=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
h=\frac{-\left(-44\right)±\sqrt{\left(-44\right)^{2}-4\times 8\times 48}}{2\times 8}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 8 for a, -44 for b, and 48 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
h=\frac{-\left(-44\right)±\sqrt{1936-4\times 8\times 48}}{2\times 8}
Square -44.
h=\frac{-\left(-44\right)±\sqrt{1936-32\times 48}}{2\times 8}
Multiply -4 times 8.
h=\frac{-\left(-44\right)±\sqrt{1936-1536}}{2\times 8}
Multiply -32 times 48.
h=\frac{-\left(-44\right)±\sqrt{400}}{2\times 8}
Add 1936 to -1536.
h=\frac{-\left(-44\right)±20}{2\times 8}
Take the square root of 400.
h=\frac{44±20}{2\times 8}
The opposite of -44 is 44.
h=\frac{44±20}{16}
Multiply 2 times 8.
h=\frac{64}{16}
Now solve the equation h=\frac{44±20}{16} when ± is plus. Add 44 to 20.
h=4
Divide 64 by 16.
h=\frac{24}{16}
Now solve the equation h=\frac{44±20}{16} when ± is minus. Subtract 20 from 44.
h=\frac{3}{2}
Reduce the fraction \frac{24}{16} to lowest terms by extracting and canceling out 8.
h=4 h=\frac{3}{2}
The equation is now solved.
8h^{2}-44h+48=0
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
8h^{2}-44h+48-48=-48
Subtract 48 from both sides of the equation.
8h^{2}-44h=-48
Subtracting 48 from itself leaves 0.
\frac{8h^{2}-44h}{8}=-\frac{48}{8}
Divide both sides by 8.
h^{2}+\left(-\frac{44}{8}\right)h=-\frac{48}{8}
Dividing by 8 undoes the multiplication by 8.
h^{2}-\frac{11}{2}h=-\frac{48}{8}
Reduce the fraction \frac{-44}{8} to lowest terms by extracting and canceling out 4.
h^{2}-\frac{11}{2}h=-6
Divide -48 by 8.
h^{2}-\frac{11}{2}h+\left(-\frac{11}{4}\right)^{2}=-6+\left(-\frac{11}{4}\right)^{2}
Divide -\frac{11}{2}, the coefficient of the x term, by 2 to get -\frac{11}{4}. Then add the square of -\frac{11}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
h^{2}-\frac{11}{2}h+\frac{121}{16}=-6+\frac{121}{16}
Square -\frac{11}{4} by squaring both the numerator and the denominator of the fraction.
h^{2}-\frac{11}{2}h+\frac{121}{16}=\frac{25}{16}
Add -6 to \frac{121}{16}.
\left(h-\frac{11}{4}\right)^{2}=\frac{25}{16}
Factor h^{2}-\frac{11}{2}h+\frac{121}{16}. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(h-\frac{11}{4}\right)^{2}}=\sqrt{\frac{25}{16}}
Take the square root of both sides of the equation.
h-\frac{11}{4}=\frac{5}{4} h-\frac{11}{4}=-\frac{5}{4}
Simplify.
h=4 h=\frac{3}{2}
Add \frac{11}{4} to both sides of the equation.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}