Answer:
see explanation
Step-by-step explanation:
Given
x² - 3x - 40 = 0
Consider the factors of the constant term (- 40) which sum to give the coefficient of the x- term (- 3)
The factors are - 8 and + 5, since
- 8 × 5 = - 40 and - 8 + 5 = - 3, thus
(x - 8)(x + 5) = 0 ← in factored form
Equate each factor to zero and solve for x
x - 8 = 0 ⇒ x = 8
x + 5 = 0 ⇒ x = 5
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Given
4x² - 81 = 0 ← this is a difference of squares and factors in general as
a² - b² = (a + b)(a - b), thus
4x² - 81
=(2x)² - 9²
= (2x + 9)(2x - 9) = 0 ← in factored form
Equate each factor to zero and solve for x
2x + 9 = 0 ⇒ 2x = - 9 ⇒ x = - 
2x - 9 = 0 ⇒ 2x = 9 ⇒ x = 
Answer:
b
Step-by-step explanation:
I mean I believe its b it looks like theres three
Answer:
r = 3.
Step-by-step explanation:
16 = 10 + √(3r + 27)
√(3r + 27) = 6
Square both sides:
3r + 27 = 36
3r = 36 - 27 = 9
r = 3.
Check the result:
Left side of the equation = 16
Right side = 10 + √(9 + 27)
= 10 + √36 = 16
Answer:
(n + 1)(3n + 7)
Step-by-step explanation:
3n² + 10n + 7
Consider the factors of the product of the n² term and the constant term which sum to give the coefficient of the n- term.
product = 3 × 7 = 21 and sum = + 10
The factors are + 3 and + 7
Use these factors to split the n- term
3n² + 3n + 7n + 7 ( factor the first/second and third/fourth terms )
3n(n + 1) + 7(n + 1) ← factor out (n + 1) from each term
= (n + 1)(3n + 7) ← in factored form
<span>The function best describes the amount she is able to put into savings, h, each year, in thousands of dollars is </span><span>h(x) = 15x + 5.</span>