Answer:
y=-x/2
Step-by-step explanation:
m=(4-1)/(-8-(-2))
m=3/-6
m=-1/2
b=y-mx
b=1-(-1/2*(-2))
b=1-1
b=0
y=-x/2
Move 12 to the other side, making it negative
h=31-12
h=19
Answer:
86%
Step-by-step explanation:
Let g represent the mean mark for the 10 girls in the class. Then the mean mark for the class was ...
10g +20(62%) = 30(70%)
g = 3(.7) -2(.62) . . . . . . . . . divide by 10 and subtract 2(.62)
g = .86 = 86%
The mean mark for girls was 86%.
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You can do this in your head if you consider it in terms of deviations from the mean. The second equation above can be rewritten and factored as ...
g = 70% +2(70% -62%)
That is, because there are 2 boys for every girl, the girl's score is above the mean by an amount that is 2 times the amount that the boy's score is below the mean. The boys' score is below by 8%, so the girls' score is above by 16%, so is 86%.
360 ÷ 12 = 30.
The measure of an interior angle of a dodecagon is 30°. (:
If you distribute -5 to the things in the parenthesis you would get 10k-20 which is the same as -5(-2k+4)