Answer:
p - a - c = b
Step-by-step explanation:
p = a + b + c
subtract a and b from both sides to isolate c
p - a - c = a - a + b
+ c - c
Answer:
E. 6
Step-by-step explanation:
Let f be the height of the fir trees
Let p be the height of the pine trees
We know from the problem that
f + p = 21 and 4f = 24 + p
rearrange the 2nd equation to get p = 4f - 24 and substitute into the other equation
so...
f + 4f - 24 = 21
5f - 24 = 21
5f = 45
f = 9 - height of the fir tree
substitute back into the 1st equation
9 + p = 21
p = 12 - height of the pine tree