Which of the following would best be solved using factoring by grouping?
1) x^2+3x- 10=0
2)3x^2+12x=8
3)x^2=25
4)x^3+ 5x^2- 9x- 45=0

ANSWER

4)x^3+ 5x^2- 9x- 45=0

EXPLANATION

Factoring by grouping is used to factor expressions that have four terms.

Among the given options, the fourth option is

There are already four terms in this expression.

So we group the first two and the last two and factor.

We can see that x² is common to the first two terms and -5 is common to the last 2 terms.

The fourth choice is correct.

6,250

step-by-step explanation:

to get the area, multiply 360 by 160.(57,600)

to find out how many bags of fertilizer it will take, first figure out how many square feet one bag can hold. divide 1000 by 8(125) to get the unit rate(how many square feet one pound of fertilizer can hold)and multiply it by 50(6250). if i haven't made a mistake, that is the answer.

2x + 8

step-by-step explanation: