Question

50pTS! What is the product?

(2x-1)(x+4)

A: 2x^2-4
B: 2x^2+4
C: 2x^2+7x-4
D: 2x^2-7x-4

Answer 1

`2x^2+7x-4` is the product of (2x-1)(x+4)

Explanation:

Given : (2x-1)(x+4)

To find =
`(2x-1)* (x+4)=?`

Solution:

`(2x-1)* (x+4)`

`(a+b)(c+d)=a(c+d)+b(c+d)`

a = 2x, b = (-1) , c = x , d = 4

`=2x(x+4)+(-1)(x+4)`

`=2x^2+8x+(-1x)+(-4)`

`=2x^2+7x-4`

`2x^2+7x-4` is the product of (2x-1)(x+4)

Answer 2

C: 2x^2+7x-4

Explanation:

(2x-1)(x+4)

FOIL

first: 2x*x = 2x^2

outer: 2x*4 = 8x

inner: -1*x = -x

last: -1*4 = -4

Add together

2x^2 +8x-x-4

2x^2 +7x-4