Answer:
m=5
Step-by-step explanation:
c=30m+50
c=20m+100
substitute
20m+100=30m+50
like terms
100-50=30m-20m
50=10m
m=5
9514 1404 393
Answer:
see attached for a graph
x = 0.5 when y = 1
Step-by-step explanation:
The graph has a y-intercept of -1, which is halfway between 0 and -2. It goes up 4 units (2 vertical grid spaces) for 1 unit to the right (1 horizontal grid space). It seems to cross y = 1 at about x = 1/2.
x = 1/2 when y = 1.
well, we know the piece-wise function is 
hmmm so what's f(-1), namely what is f(x) when x = -1?
well, when x = -1, hmm -1 is less than 0, so the subfunction that applies to that will be when "x" is less than 0, namely the part of 7x + 10, so we can say
f(-1) = 7(-1) + 10
f(-1) = 3
so hmm what's f(0) or namely, what's f(x) when x = 0?
well, what subfunction applies when x = 0? well, it has to be the subfunction with "x greater or <u>equals</u> to 0", x ⩾ 0, so then is 7x + 20
f(0) = 7(0) + 20
f(0) = 20.

Hope you could get an idea from here.
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