For those who may still need it in the future, the correct answer is actually: D: 3(x^2 + 1) +2
Answer:
second option
Step-by-step explanation:
Given
+ 6x² + 5 = 0
let u = x², then
u² + 6u + 5 = 0 ← in standard form
(u + 1)(u + 5) = 0 ← in factored form
Equate each factor to zero and solve for u
u + 1 = 0 ⇒ u = - 1
u + 5 = 0 ⇒ u = - 5
Change u back into terms of x, that is
x² = - 1 ( take the square root of both sides )
x = ±
= ± i ( noting that
= i ), and
x² = - 5 ( take the square root of both sides )
x = ±
= ±
= ±
×
= ± i
Solutions are x = ± i and x = ± i
Same question
x+y=30
x is 1/5 of y
x=y/5
subsitute
y/5+y=30
multily both sidse by 5
y+5y=150
add
6y=150
divide both sides by 6
y=25
subsitute
x=y/5
x=25/5
x=5
the numbers are 5 and 25
12 is a factor of 36 and of course 12, so
Answer: 12