196k views
13 votes
Please show me the steps of solving this and the answer 2n² +3n-9

User Khyox
by
4.3k points

1 Answer

7 votes

Answer: n=-3 and n=3/2

Explanation:

To solve the expression, we want to find the values of n. Since there are no common factors in 2, 3, -9, we directly multiply the "a" and "c" values.

2×(-9)=-18

This means, we want to find two numbers that multiply to -18 and adds to 3. This can also be known as the cross method.

We will find that 6 and -3 multiply to -18, and adds to 3.

In our box method, we want to find the common factors.

|2n²|6n|

|-3n|-9|

Note: Just pretend the lines line up and form a square box, with a term in each box.

After finding that is in common between the boxes, we get (n+3)(2n-3)=0

To solve, we set each factor equal to 0.

n+3=0

n=-3

2n-3=0

2n=3

n=3/2

User Arctelix
by
4.4k points