2(x

^{2}-1)=7x+13 solve an sum of two roots2(x^{2}-1)=7x+13 solve an sum of two roots

Tutors, please sign in to answer this question.

Westford, MA

If a(x-b)(x-c)=0,

then ax^2 - a(b+c)x + bc = 0.

The sum of the two roots is the opposite of the coefficient of the linear term divided by the leading coefficient.

Tom's 3rd line is 2x^2 - 7x -15 = 0.

We can immediately say the sum of the roots is 7/2.

Sarasota, FL

2(x^2 -1) = 7x + 13

2x^2 - 2 = 7x +13

2x^2 - 7x -15 = 0

Factoring we get

(2x + 3) (x - 5) = 0

2X + 3 =0

2X = -3

X = -3/2

AND

x - 5 =0

x = 5

Tara W.

High school physics & engineering teacher, 17 yrs experience

New York, NY

5.0
(15 ratings)

Amaan M.

Math/Economics Teacher

New York, NY

5.0
(69 ratings)

Dana R.

English/Math SAT PrepTutor with PhD

Lynbrook, NY

4.8
(85 ratings)

- Algebra 1 3926
- Math 9335
- Algebra 4881
- Math Help 5169
- Algebra Word Problem 2401
- Precalculus 1477
- Word Problem 4933
- Algebra 2 Question 499
- Algebra Help 952
- Geometry 1805