Question

Multiply r2+7r+10/3 by 3r-30/ r2-5r-50

Answer 1

((r²+7r+10)/3) × (3r-30)/(r²-5r=50)
= Factoring the expression (r²+7r+10) we get  (r+2)(r+5)
Then multiply it with the other numerator, we get
= (r+2)(r+5)(3(r-10)
Then we factorise
= (r²-5r-50) = (r+5)(r-10)
Multiplying it with the other denominator, we have;
= 3(r+5)(r-10)
Therefore dividing

(r+2)(r+5)(3(r-10)/(3(r+5)(r-10) we get;
= r+2
Therefore, the correct answer is r+2

Answer 2

(r+5)(r+2)/3  *   3(r-10)/(r-10)(r+5)

If you eliminate the (r+5),(r-10) and 3, then what is left is (r+2). The answer is r+2.