Solve for r
r=0
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7\left(r-4\right)=4\left(r-7\right)
Variable r cannot be equal to 7 since division by zero is not defined. Multiply both sides of the equation by 7\left(r-7\right), the least common multiple of r-7,7.
7r-28=4\left(r-7\right)
Use the distributive property to multiply 7 by r-4.
7r-28=4r-28
Use the distributive property to multiply 4 by r-7.
7r-28-4r=-28
Subtract 4r from both sides.
3r-28=-28
Combine 7r and -4r to get 3r.
3r=-28+28
Add 28 to both sides.
3r=0
Add -28 and 28 to get 0.
r=0
Product of two numbers is equal to 0 if at least one of them is 0. Since 3 is not equal to 0, r must be equal to 0.
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