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Question 2.7T2:(Please help!!)

Question should be attached!

Question 2.7T2:(Please help!!) Question should be attached!-example-1
User Szhem
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1 Answer

16 votes
16 votes

Answer:

x = - 6, x =
(4)/(5)

Explanation:

set w(x) = g(x) , that is

2x² + 6x - 5 = - 3x² - 20x + 19 ( add 3x² to both sides )

5x² + 6x - 5 = - 20x + 19 ( add 20x to both sides )

5x² + 26x - 5 = 19 ( subtract 19 from both sides )

5x² + 26x - 24 = 0 ← in standard form

to factorise the expression

consider 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 × - 24 = - 120 and sum = + 26

the factors are + 30 and - 4

use these factors to split the x- term

5x² + 30x - 4x - 24 = 0 ( factor the first/second and third/fourth terms )

5x(x + 6) - 4(x + 6) = 0 ← factor out (x + 6) from each term

(x + 6)(5x - 4) = 0 ← in factored form

equate each factor to zero and solve for x

x + 6 = 0 ⇒ x = - 6

5x - 4 = 0 ⇒ 5x = 4 ⇒ x =
(4)/(5)

User Lawrence Barsanti
by
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