Skip to main content
Solve for q
Tick mark Image

Similar Problems from Web Search

Share

qq+2=-3q
Variable q cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by q.
q^{2}+2=-3q
Multiply q and q to get q^{2}.
q^{2}+2+3q=0
Add 3q to both sides.
q^{2}+3q+2=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=3 ab=2
To solve the equation, factor q^{2}+3q+2 using formula q^{2}+\left(a+b\right)q+ab=\left(q+a\right)\left(q+b\right). To find a and b, set up a system to be solved.
a=1 b=2
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. The only such pair is the system solution.
\left(q+1\right)\left(q+2\right)
Rewrite factored expression \left(q+a\right)\left(q+b\right) using the obtained values.
q=-1 q=-2
To find equation solutions, solve q+1=0 and q+2=0.
qq+2=-3q
Variable q cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by q.
q^{2}+2=-3q
Multiply q and q to get q^{2}.
q^{2}+2+3q=0
Add 3q to both sides.
q^{2}+3q+2=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=3 ab=1\times 2=2
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as q^{2}+aq+bq+2. To find a and b, set up a system to be solved.
a=1 b=2
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. The only such pair is the system solution.
\left(q^{2}+q\right)+\left(2q+2\right)
Rewrite q^{2}+3q+2 as \left(q^{2}+q\right)+\left(2q+2\right).
q\left(q+1\right)+2\left(q+1\right)
Factor out q in the first and 2 in the second group.
\left(q+1\right)\left(q+2\right)
Factor out common term q+1 by using distributive property.
q=-1 q=-2
To find equation solutions, solve q+1=0 and q+2=0.
qq+2=-3q
Variable q cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by q.
q^{2}+2=-3q
Multiply q and q to get q^{2}.
q^{2}+2+3q=0
Add 3q to both sides.
q^{2}+3q+2=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.
q=\frac{-3±\sqrt{3^{2}-4\times 2}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 3 for b, and 2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
q=\frac{-3±\sqrt{9-4\times 2}}{2}
Square 3.
q=\frac{-3±\sqrt{9-8}}{2}
Multiply -4 times 2.
q=\frac{-3±\sqrt{1}}{2}
Add 9 to -8.
q=\frac{-3±1}{2}
Take the square root of 1.
q=-\frac{2}{2}
Now solve the equation q=\frac{-3±1}{2} when ± is plus. Add -3 to 1.
q=-1
Divide -2 by 2.
q=-\frac{4}{2}
Now solve the equation q=\frac{-3±1}{2} when ± is minus. Subtract 1 from -3.
q=-2
Divide -4 by 2.
q=-1 q=-2
The equation is now solved.
qq+2=-3q
Variable q cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by q.
q^{2}+2=-3q
Multiply q and q to get q^{2}.
q^{2}+2+3q=0
Add 3q to both sides.
q^{2}+3q=-2
Subtract 2 from both sides. Anything subtracted from zero gives its negation.
q^{2}+3q+\left(\frac{3}{2}\right)^{2}=-2+\left(\frac{3}{2}\right)^{2}
Divide 3, the coefficient of the x term, by 2 to get \frac{3}{2}. Then add the square of \frac{3}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
q^{2}+3q+\frac{9}{4}=-2+\frac{9}{4}
Square \frac{3}{2} by squaring both the numerator and the denominator of the fraction.
q^{2}+3q+\frac{9}{4}=\frac{1}{4}
Add -2 to \frac{9}{4}.
\left(q+\frac{3}{2}\right)^{2}=\frac{1}{4}
Factor q^{2}+3q+\frac{9}{4}. 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(q+\frac{3}{2}\right)^{2}}=\sqrt{\frac{1}{4}}
Take the square root of both sides of the equation.
q+\frac{3}{2}=\frac{1}{2} q+\frac{3}{2}=-\frac{1}{2}
Simplify.
q=-1 q=-2
Subtract \frac{3}{2} from both sides of the equation.