1/x + 1/y = 8
x + y = 8
6/x + 12/y = 72n
Answer:
A point on either side of the line
Step-by-step explanation:
To determine which side to shade, you look at a point on each side of the line. One will make the inequality true and one will not. Shade on the side that will make the inequality true
Answer:
x = 2 sqrt(3) or x = -2 sqrt(3) or x = sqrt(3) or x = -sqrt(3)
Step-by-step explanation:
Solve for x:
-8 + x^2 + (x^2 - 8)^2 = 20
Expand out terms of the left hand side:
x^4 - 15 x^2 + 56 = 20
Subtract 20 from both sides:
x^4 - 15 x^2 + 36 = 0
Substitute y = x^2:
y^2 - 15 y + 36 = 0
The left hand side factors into a product with two terms:
(y - 12) (y - 3) = 0
Split into two equations:
y - 12 = 0 or y - 3 = 0
Add 12 to both sides:
y = 12 or y - 3 = 0
Substitute back for y = x^2:
x^2 = 12 or y - 3 = 0
Take the square root of both sides:
x = 2 sqrt(3) or x = -2 sqrt(3) or y - 3 = 0
Add 3 to both sides:
x = 2 sqrt(3) or x = -2 sqrt(3) or y = 3
Substitute back for y = x^2:
x = 2 sqrt(3) or x = -2 sqrt(3) or x^2 = 3
Take the square root of both sides:
Answer: x = 2 sqrt(3) or x = -2 sqrt(3) or x = sqrt(3) or x = -sqrt(3)
Answer:
d = -16
Step-by-step explanation:
Step 1: Write equation
89 = -5d + 9
Step 2: Solve for <em>d</em>
<u>Subtract 9 on both sides:</u> 80 = -5d
<u>Divide both sides by -5:</u> -16 = d
Step 3: Check
<em>Plug in x to verify if it's a solution.</em>
89 = -5(-16) + 9
89 = 80 + 9
89 = 89
Answer:
x=4.63
Step-by-step explanation:
Area = (1/2) (base) (height)
20 = (1/2) (x+4) (x)
40 = x²+4x
x²+4x-40=0
Put in quadratic equation:
x=
x=
x=4.63324958071 or x=-8.63324958071
Since x can't be negative in this case we take our answer to be 4.63324958071, which rounds to 4.63
