Answer:
a) 1/2; reduction
b) 5/4; enlargement
Step-by-step explanation:
In each case, the scale factor is CP'/CP. When it is more than 1, the dilation is an enlargement.
Even before you run the numbers, you can tell if it is an enlargement or not. If the dilated figure is larger, P is closer to C than is P'. If P' is closer to C, then it is a reduction.
a) CP'/CP = (4-2)/4 = 2/4 = 1/2 . . . . a reduction
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b) CP'/CP = 25/20 = 5/4 . . . . an enlargement
Hj and jk are the same length line segments ( because the midpoint divides a line into two equal parts)
So hj = jk.
hk is the line segment which has the mid point j. It is the double of hj or jk. It can be the sum of hj and jk.
hj + jk = hk
or
2 * hj = hk
or
2 * jk = hk
61 = 3b + 7
3b + 7 = 61
3b = 61 - 7
3b = 54
b = 54/3
b = 18.