Answer:
x= 6
Step-by-step explanation:
12+3x=30
3x+12=30
3x+12-12=30-12
3x=30-12
3x=18
3x divided by 3 = 18 divided by 3
x=18 over 3
18 divided by 3 is 6
x=6
She needs to score a 91 on her next test because 85+78+77+69+91=400 and 400 divided by 5 gives you a mean of 80.
Answer:
942 cubic feet
Step-by-step explanation:
Length of one edge is 10cm
And the surface area is 600cm2
1. Use the Pythagoras theorem
13^2 = x^2 + 5^2
solve for x and youll get the height of the roof.
2. let x = length of the rpoe)-
x^2 = 9^2 + 12^2
3. Pythagoras again
20^2 = x^2 + 12^2