(R+11) (R-7) = 0, find the value of R
Answers
Answer:
step by step explanation is below
Step-by-step explanation-
Factoring r2-11r+28
The first term is, r2 its coefficient is 1 .
The middle term is, -11r its coefficient is -11 .
The last term, "the constant", is +28
Step-1 : Multiply the coefficient of the first term by the constant 1 • 28 = 28
Step-2 : Find two factors of 28 whose sum equals the coefficient of the middle term, which is -11 .
-28 + -1 = -29
-14 + -2 = -16
-7 + -4 = -11 That's it
Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -7 and -4
r2 - 7r - 4r - 28
Step-4 : Add up the first 2 terms, pulling out like factors :
r • (r-7)
Add up the last 2 terms, pulling out common factors :
4 • (r-7)
Step-5 : Add up the four terms of step 4 :
(r-4) • (r-7)
Which is the desired factorization