what do you need help with
Answer:
A = P * a / 2
A = 81.25
Step-by-step explanation:
We have that there is a corresponding formula for a regular decagon, which depends on the apothem and the perimeter, it is the following:
A = P * a / 2
In this case, the perimeter is the sum of all the sides, that is, 10 sides, therefore:
P = 10 * 3.25
P = 32.5 meters
We replace:
A = 32.5 * 5/2
A = 81.25
Which means that for that regular decagon, the area is 81.25 square meters.
Answer:
90
Step-by-step explanation:
3 hours = 180 mins
180 ÷ 45 = 4. so Ellie will drive 4x more miles in 3 hours.
22.5 × 4 = 90
Answer:
(using substitution to solve the problem)
x=y-3
2x+y=12
2(y-3)+y=12
2y-6+y=12
3y=18
y=6
y=6
x=6-3
= (3, 6)
Step-by-step explanation:
using substitution, substitute the x in the second equation to y-3, to find the value of y. after that distribute the 2 into the parenthesis and collect like terms. once you simplify, you have the value of y, so substitute the value of y into the first equation to find x. once you have both values put them in the ordered pair form and you're done.
i hope this helps :)
