Solve for all values of x by factoring.

x^2-20x+72=-3x

x = 9, 8

Step-by-step explanation:

1) To find all values of x by factoring, move all the terms to one side, setting them to zero. So, add both sides by -3x to move the term:

2) Now, factor the expression. The product of -8 and -9 equals 72, and adding the two numbers together equals -17. So, the factored expression must be (x-9) (x-8):

3) Look at the expressions in the parentheses. Whatever values of x that makes each expression equal 0 will be the answer. Thus, x must equal 9 and 8.

d. bc = 12 and ef = 16

step-by-step explanation:

we are given that δabc : δdef such that .

also, it is given that

so, from the options, we need that .

a.

b.

c.  

d.

as, we can see that only option d gives the same ratio as i.e. .

hence, the possible lengths are bc = 12 and ef = 16.