Answer:
40°
Step-by-step explanation:
Angle 1 and Angle 2 are corresponding angles.
Corresponding angles are congruent, so 3x + 4 = 5x - 20
Solving 3x + 4 = 5x - 20
3x = 5x - 24
2x = 24
x = 12
Substitute angle 1
3x + 4 = 36 + 4 = 40
Answer:
20
Step-by-step explanation:
→ First find the value of x and y
x + y = 5
x - y = 4
→ Add the equations to cancel out the y's
2x = 9
→ Divide both sides by 2 to find the value of x
x = 4.5
→ Substitute x = 4.5 back into x - y = 4 to find the value of y
4.5 - y = 4
→ Minus 4.5 from both sides to isolate -y
-y = -0.5
→ Multiply everything by -1
y = 0.5
→ Substitute x = 4.5 and y = 0.5 into x² - y²
4.5² - 0.5² = 20.25 - 0.25 = 20
Answer:
2.29 ft of side length and 1.14 height
Step-by-step explanation:
a) Volume V = x2h, where x is side of square base and h is hite.
Then surface area S = x2 + 4xh because box is open.
b) From V = x2h = 6 we have h = 6/x2.
Substitude in formula for surface area: S = x2 + 4x·6/x2, S = x2 + 24/x.
We get S as function of one variable x. To get minimum we have to find derivative S' = 2x - 24/x2 = 0, from here 2x3 - 24 = 0, x3 = 12, x = (12)1/3 ≅ 2.29 ft.
Then h = 6/(12)2/3 = (12)1/3/2 ≅ 1.14 ft.
To prove that we have minimum let get second derivative: S'' = 2 + 48/x3, S''(121/3) = 2 + 48/12 = 6 > 0.
And because by second derivative test we have minimum: Smin = (12)2/3 + 4(12)1/3(12)1/3/2 = 3(12)2/3 ≅ 15.72 ft2
Answer:
-x+11
Step-by-step explanation:
am not sure if this is correct but
2x-3x=-x
-7+18=11
-x+11
