Answer:
x = 2±sqrt(11)
Step-by-step explanation:
x^2 -4x - 7 =0
Add 7 to each side
x^2 -4x -7+7 =0+7
x^2 -4x =7
To complete the square take the coefficient of the x term and divide by 2 and then square it. Add it to both sides
-4 /2 = -2 then square
(-2)^2 = 4
Add 4 to both sides
x^2 -4x+4 =7+4
x^2 -4x+4 = 11
Factor the left side into (x-b/2)^2
(x-2)^2 =11
Take the square root of each side
sqrt((x-2)^2) =±sqrt(11)
x-2 = ±sqrt(11)
Add to to each side
x-2+2 = 2±sqrt(11)
x = 2±sqrt(11)
Answer:
m∠ABD = 88º
m∠CBD = 23º
Step-by-step explanation:
(-10x + 58) + (6x + 41) = 111
Combine like terms
-4x + 99 = 111
Subtract 99 from both sides
-4x = 12
Divide both sides by -4
x = -3
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m∠ABD = -10x + 58
m∠ABD = -10(-3) + 58
m∠ABD = = 30 + 58
m∠ABD = 88º
m∠CBD = 6x + 41
m∠CBD = 6(-3) + 41
m∠CBD = -18 + 41
m∠CBD = 23º
Answer:
-0.574
Step-by-step explanation:
Subtract the two numbers to get the solution
Answer:
8 x + 25y ≥100
x+y ≤ 14
Step-by-step explanation:
Hi, to answer this question we to write a system of inequalities.
First inequality:
The product of the earnings per hour working at culvers (8) and the number of hours worked there, plus the product of the earnings per hour mowing lawns (8) and the number of hours mowing must be greater or equal to $100.
Second inequality:
The amount of time he works at culvers (x) plus the amount of time he works mowing lawn (y) must be less or equal to 14 hours.
8 x + 25y ≥100
x+y ≤ 14
Where:
x = number of hours worked at Culvers
y= number of hours worked Mowing lawns