Question

(a-8)(a+7)-(a+10)(a-11)

Answer 1

(a-8)(a+7) - (a+10)(a-11) = a^2-a-56 - (a^2-a-110) = a^2-a-56-a^2+ a+110 = 54

Answer 2

To simplify the expression, let's expand it step by step:

Step 1: Expand the first bracket (a - 8)(a + 7): (a - 8)(a + 7) = a * a + a * 7 - 8 * a - 8 * 7 = a^2 + 7a - 8a - 56 = a^2 - a - 56

Step 2: Expand the second bracket (a + 10)(a - 11): (a + 10)(a - 11) = a * a + a * (-11) + 10 * a - 10 * 11 = a^2 - 11a + 10a - 110 = a^2 - a - 110

Now, let's put both expanded expressions back into the original expression and combine like terms:

(a - 8)(a + 7) - (a + 10)(a - 11) = (a^2 - a - 56) - (a^2 - a - 110)

When we distribute the negative sign to the second bracket, all its terms change signs:

= a^2 - a - 56 - a^2 + a + 110

Now, notice that the squared term (a^2) cancels out:

= -a + a - 56 + 110

The 'a' term also cancels out:

= 54

So the simplified expression is 54.