X=12.5
If the perimeter is 90
90=3x+3x+15
Combine like terms
90=6x+15
Subtracts 15 from both sides
75=6x
Divide by six to get x by itself
12.5=x
Does this help?
Answer:
m = 0
Step-by-step explanation:

Answer:
D
Step-by-step explanation:
It's the only thing not listed aka the number of math problems.
Answer: Santa's speed in still air is 6 miles per minute
Speed of the wind is 1 mile per minute
Step-by-step explanation:
Let x represent the speed of Santa in still air. It is assumed that in still air. She is flying with the wind. If the speed of the wind is y, then him total speed is x + y
It takes Santa 5 minutes to fly 35 miles with the wind.
Speed = distance / time
It means that
x + y = 35/5 = 7
It takes him 7 minutes to fly 35 miles against the wind. This means that his total speed will be x - y
Speed = distance/time. Therefore,
x - y = 35 /5 = 5 - - - - - - 1
Substituting x = 7 - y into equation 1, it becomes
7 - y - y = 5
-2y = 5 - 7 = -2
y = -2/-2 = 1
x = 7 - y = 7 - 1
x = 6
Answer:
∠B = 60°
Step-by-step explanation:
They are supplementary angles, which means they add up to 180°.
∠B + ∠A = 180
? + 120 = 180
? = 180 - 120
? = 60°