Answer:
x = -2 ± sqrt(5)
Step-by-step explanation:
x^2 + 4x – 1= 0
Add 1 to each side
x^2 + 4x – 1+1= 0+1
x^2 +4x = 1
Take the coefficient of x
4
Divide by 2
4/2 =2
Square it
2^2=4
Add it to each side
x^2 +4x+4=1+4
(x+2)^2 = 5
Take the square root of each side
sqrt((x+2)^2 )=± sqrt(5)
x+2 = ± sqrt(5)
Subtract 2 from each side
x+2-2 = -2 ± sqrt(5)
x = -2 ± sqrt(5)
Answer:
vertex = (- 1, 3 )
Step-by-step explanation:
Given a parabola in standard form
y = ax² + bx + c ( a ≠ 0 )
Then the x- coordinate of the vertex is
= - 
y = 2x² + 4x + 5 ← is in standard form
with a = 2, b = 4, then
= - 
= - 1
Substitute x = - 1 into the equation for corresponding value of y, that is
y = 2(- 1)² + 4(- 1) + 5 = 2 - 4 + 5 = 3
vertex = (- 1, 3 )
Answer:
^^1 week and 5 days
Explanation:
If she has $85 now, and gains $10 per week, by the next week and 5 days, she should have her goal of $205. Hope it helps!
Answer:
y = x + 1
Step-by-step explanation:
We are using the points (0, 1) and (6, 7). First, use these points to find the slope.
m = y₁ - y₂/x₁ - x₂
⇒ m = 7 - 1/6 - 0
⇒ m = 6/6
⇒ m = 1
Now that we know the slope is one, enter the values into the point-slope form equation. I'll use (0, 1) in this instance.
y - y₁ = m(x - x₁)
⇒ y - 1 = 1(x - 0)
⇒ y - 1 = x
⇒ y = x + 1
Therefore, the equation is y = x + 1.
