The old mean was 51 now the mean is 42.33... (round that to 42) 51 - 42 = 9
Answer:
Arithmetic
Step-by-step explanation:
A = L * W = 75 so L = 75/W Cost = 4W + 8(2L + W) = 4W + 16L + 8W = 12W + 16L = 12W + 1200/W C' = (12(W^2 - 100))/(W^2) = (12(W-10)(W+10))/(W^2) so W = 10 then L = 7.5
Answer:
t=40
Step-by-step explanation:
The sum of all angles in a triangle will always equal 180°. This means that:
(2t-42)+(4t-49)+(2t-49) = 180°
Let's solve this equation!
(2t-42)+(4t-49)+(2t-49) = 180
First we simplify what's on the left side:
2t-42+4t-49+2t-49 = 180
2t+4t+2t-42-49-49 = 180
8t-140 = 180
*Add 140 to both sides
8t = 180+140
8t = 320
Divide both sides by 8 to know what t means:
t = 320/8
t = 40