. Jin writes an expression to describe the number of wolves in Year 4 of the
study. The expression is (x+a)(x-b), where a and b are whole numbers
greater than 1 and less than 10. Write an expression that could be the
expression Jin uses to describe the number of wolves in the park during
Year 4 of the study. Then multiply the two terms of the expression.
One possible expression Jin could have used is (x+5)(x-3).
When we multiply the two terms of this expression:
(x+5)(x-3) = x(x) + x(-3) + 5(x) + 5(-3)
= x^2 - 3x + 5x - 15
= x^2 + 2x - 15
Therefore, the expression Jin used to describe the number of wolves in Year 4 could be x^2 + 2x - 15.