Factor each polynomial
4z^2+4z-15

(2z+5) (2z-3)

Step-by-step explanation:

First, multiply the first coefficient by the third.

4*-15=-60

Then find factors of -60 that add up to the middle term.

The factors are: -6 and 10-------> -6*10=-60 and -6+10=4 so -6 and 10 are the correct factors.

Break up the middle term with the factors that you got above. The new equation will be: 4-6z+10z-15

Factor by grouping.

First, break the equation into two

(4-6z) (10z-15)

Then, factor out the greatest number you can

2z(2z-3) 5(2z-3)

You are then left with a common binomial of 2z-3. COmbine the common binomial into 1 and combine the 2 numbers you factored out in the step above (2z and 5) The final equation will be this:

(2z+5) (2z-3)

tip $2.90

total $17.40