Answer:
B 41.4
Step-by-step explanation:
complete Pythagoras for general triangles :
c² = a² + b² - 2ab×cos(C)
with "c" being the side opposite of the angle C.
=>
8² = 10² + 12² - 2×10×12×cos(C)
64 = 244 - 240×cos(C)
240×cos(C) = 244 - 64 = 180
cos(C) = 180/240 = 18/24 = 3/4 = 0.75
C = 41.40962211... ≈ 41.4
In order for the triangle to be isosceles, we have to set two lengths of the triangle equal to each other.
Let's take the lengths 5x-12 and x+20 and set them equal to each other.
5x - 12 = x + 20
Combine like terms by moving them over to their respective sides.
Subtract x from both sides of the equation.
4x - 12 = 20
Add 12 to both sides of the equation.
4x = 32
Divide both sides by 4.
x = 8
Check your answer by substituting.
5x - 12 = x + 20
5(8) - 12 = 8 + 20
40 - 12 = 28
28 = 28
Solution: x = 8
For number 16 we need to write the data as a ratio then convert to a unit rate (amount per 1)...
308/14 = x/1
Cross multiply
14x = 308
x = 308/14
x = 22
So the fuel efficiency is
22 miles per 1 gallon or
22/1
For number 17, since the car was driven at 48 mph, we just have to divide distance driven by speed to get how long it took...
288 miles ÷ 48 mph =
6 hours
Answer:
122°F
Step-by-step explanation:
F=(50×9/5)+32
= 122°F
Step-by-step explanation:
4x+2x+x+9x=16x
16x=2+5+4=11
x=11