1) Let's write out both expressions subtracting 4m²+2mn+8n² from 2m²+6mn+2n²
2) Note that when we subtract 4m^2 + 2mn + 8n^2 from 2m^2 + 6mn + 2n^2 we need to swap the sign by placing -1 outside the parentheses and then combine like terms adding those terms algebraically.
Let's start with a picture.
We see RST is smaller, and BC is parallel to but in the opposite direction to its corresponding segment ST. Both have slope -1.
If we look at the difference of points (technically called vectors but we don't have to go there) we get
C-B=(-2,2)
T-S=(1,-1)
Without further calculation we can see T-S is half the length of C-B.
The problem asks for a dilation followed by a reflection. We know the dilation scale is k=1/2 because the new triangle is half the size.
After dilation we get A'B'C':
A'(3,2), B'(-1,0), C'(-2,1)
We see now we need a reflection that flips the coordinates x and y. That's the +45° line through the origin, namely y=x.
Answer: k=1/2, y=x
Answer:
for four copies the cost is $72
Step-by-step explanation:
52 + 5a = 24 + 12a
28 + 5a = 12a
28 = 7a
a = 4
52 + 20 = 72
for four copies the cost is $72
