Question

(8x 2 −15x)−(x 2 −27x)=ax 2 +bxleft parenthesis, 8, x, squared, minus, 15, x, right parenthesis, minus, left parenthesis, x, squared, minus, 27, x, right parenthesis, equals, a, x, squared, plus, b, x If the equation above is true for all values of xxx, what is the value of b-ab−ab, minus, a ?

Answer 1

Answer:

5

Step-by-step explanation:

Given the expression (8x² −15x)−(x² −27x) = ax² +bx, we are to determine the value of b-a. Before we determine the vwlue of b-a, we need to first calculate for the value of a and b from the given expression.

On expanding the left hand side of the expression we have;

= (8x² −15x)−(x² −27x)

Open the paranthesis

= 8x² −15x−x²+27x

collect the like terms

= 8x²−x²+27x −15x

=  7x²+12x

Comparing the resulting expression with ax²+bx

7x²+12x =  ax²+bx

7x² = ax²

a = 7

Also;

12x = bx

b =12

The value of b - a = 12 - 7

b -a = 5

Hence the value of b-a is equivalent to 5