Question

The answer to the first question.

Answer 1

Answer:?

Step-by-step explanation: what am I exactly reading it would better help if you typed it.

Answer 2

see explanation

Explanation:

Given

5x² - 4 - 8x

To find the zeros equate to zero and rearrange into standard form, that is

5x² - 8x - 4 = 0 ← in standard form

To factor the quadratic

Consider the factors of the product of the coefficient of the x² term and the constant term which sum to give the coefficient of the x- term.

product = 5 × - 4 = - 20 and sum = - 8

The factors are - 10 and + 2

Use these factors to split the x- term

5x² - 10x + 2x - 4 = 0 ( factor the first/second and third/fourth terms )

5x(x - 2) + 2(x - 2) = 0 ← factor out (x - 2) from each term

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

Equate each factor to zero and solve for x

x - 2 = 0 ⇒ x = 2

5x + 2 = 0 ⇒ 5x = - 2 ⇒ x = -
`(2)/(5)`

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The sum of the zeros = -
`(b)/(a)`

The product of the zeros =
`(c)/(a)`

with a = 5, b = - 8 and c = - 4

The sum = 2 -
`(2)/(5)` =
`(8)/(5)`

and -
`(b)/(a)` = -
`(-8)/(5)` =
`(8)/(5)`

Thus verified

The product = 2 × -
`(2)/(5)` = -
`(4)/(5)`

and
`(c)/(a)` =
`(-4)/(5)` = -
`(4)/(5)`

Thus verified