Answer:
see explanation
Step-by-step explanation:
x² + 3x + 7 = 5 ( subtract 5 from both sides )
x² + 3x + 2 = 0 ← in standard form
(x + 2)(x + 1) = 0 ← in factored form
Equate each factor to zero and solve for x ( zero product rule )
x + 2 = 0 → x = - 2
x + 1 = 0 ⇒ x = - 1
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x² - 2 = - 2x² + 5x ( subtract - 2x² + 5x from both sides )
3x² - 5x - 2 = 0 ← in standard form
(3x + 1)(x - 2) = 0 ← in factored form
Equate each factor to zero and solve for x
3x + 1 = 0 ⇒ 3x = - 1 ⇒ x = - 
x - 2 = 0 ⇒ x = 2
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(x + 3)² + 4x = 0 ← expand left side using FOIL and simplify
x² + 6x + 9 + 4x = 0
x² + 10x + 9 = 0 ← in standard form
(x + 9)(x + 1) = 0 ← in factored form
Equate each factor to zero and solve for x
x + 9 = 0 ⇒ x = - 9
x + 1 = 0 ⇒ x = - 1
Answer:
b = 
Step-by-step explanation:
To clear the radicals square both sides
=
( cross- multiply )
(6 - a)(8 + b) = b - 7 ← expand factors on left using FOIL
48 + 6b - 8a - ab = b - 7 ( subtract 48 from both sides )
6b - 8a - ab = b - 55 ( add 8a to both sides )
6b - ab = b - 55 + 8a ( subtract b from both sides )
6b - ab - b = 8a - 55, that is
5b - ab = 8a - 55 ← factor out b from each term on the left side )
b(5 - a) = 8a - 55 ← divide both sides by (5 - a)
b = 
C
14²+21²-√49
196+441-7
630
Mark brainliest please
It will be 89 because 27+17+15+13+8+3+6