Question

Which values of a and b make the following equation true?  a = 11, b = 7 a = 11, b = 10 a = 28, b = 7 a = 28, b = 10

Answer 1

a = 11, b = 7
You just needed to multiply the terms together

Answer 2

we have

`(5x^(7) y^(2))(-4 x^(4) y^(5))=-20 x^(a) y^(b)`

Multiply the terms of the left side of the equation and then compare with the right side to find the values of a and b

`(5x^(7) y^(2))(-4 x^(4) y^(5))=-20 x^((7+4)) y^((2+5))`

`=-20 x^(11) y^(7)`

substitute

`-20 x^(11) y^(7)=-20 x^(a) y^(b)`

Solve for a

`x^(11) =x^(a)`

`a=11`

Solve for b

`y^(7) =y^(b)`

`b=7`

therefore

the answer is

`a=11`

`b=7`