Answer:
15
Step-by-step explanation:
If A||B then the sum of given angles must be equal to 180°
2x + 5 + 5x - 80 = 180 add like terms
7x - 75 = 180 subtract 75 from both sides
7x = 105 divide both sides by 7
x = 15
No because there is no picture and circles
r = radius
Arc length = 2(3.14)r
7.9 cm = r
Plug our values in
Arc length = 2(3.14)(7.9 cm)
Arc length = 49.6 cm
Answer:
x=10 or x=-2
Step-by-step explanation:
add 28 to both sides
(x-4)^2=36
sqrt both sides
remember to get positive and negative roots
x-4=+/-6
add 4 to both sides
x=4+/-6
x=4+6 or x=4-6
We can find the answer by solving the two equations simultaneously.
equation 1: y = -0.4x^2 +3xequation 2: x + y = 10
We need to write equation to with y as the subject:equation 2: y = 10 - x
equation 1 = equation 2:
10 - x = -0.4x^2 + 3x0.4x^2 - 4x + 10 = 02x^2 - 20 + 50 = 0(2x - 10)(x - 5) = 0x = -10/2 or x = 5
<span>But x >= 0 (the question says it's a height </span>above<span> the water), so x = 5</span>
Substituting x = 5 into one of the equations:
y = 10 - x
y = 10 - 5
y = 5
<span>So the answer is C</span>
