Factor the expression. 49x^2-16 a. (7x + 4)(7x − 4) b. (7x − 4)(7x − 4) c. (4x + 7)(4x − 7) d. (4x − 7)(4x − 7)

The correct answer is first option

(7x + 4)(7x − 4)

Step-by-step explanation:

Points to remember

Identities

(a + b)(a - b) = a² - b²

It is given an expression,

49x² - 16

To factorize  the expression 49x² - 16

We know that 7² = 49 and 4² = 16

Therefore we can write the given expression as,

49x² - 16 = (7x)² - 4²

It is in the form of the above identity,

(7x)² - 4² = (7x + 4)(7x - 4)

The correct answer is first option

there are lots of ways.   pick's theorem tells us if the vertices are lattice points the area a is

a = b/2 + i - 1

where b is the number of boundary lattice points and i is the number of interior lattice points.

in the figure i count b=16, i=50 so

a = 8 + 50 - 1 = 57

let's try the shoelace formula.   the area is half the sum of the cross products of the sides.  

a(-2,6)   -2(2)-6(-5) = 26

b(-5,2)   -5(-3) - 2(-2) = 19

c(-2,-3) -2(-3) - (-3)(4) = 18

d(4,-3)   4(3) - (-3)(5) = 27

e(5,3)   5(3) - 3(1) = 12

f(1,3)     1(6) - 3(-2) = 12

a(-2,6)

each of the cross products is twice the area of the triangle with the associated side and one vertex the origin. so the area of abo=26/2=13.

area = (1/2) (26 + 19 +   18 + 27 + 12 + 12) = 57

that checks!

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6 purchases

if you are asking how many of each then:

18 social media ads

6 newspaper ads