Use △GHJ, where A, B, and C are midpoints of the sides.
When GH = 7z−1 and CB = 4z−3, what is GA?

Answer:
GA=17
Step-by-step explanation:
As A, B, C are the midpoints of the sides of AGHJ,
so GH= 2(CB)
⇒7z-1= 2(4z-3)
⇒7z-1= 8z-6
⇒7z-8z= -6+1
⇒-7= -5
z=5
so GA=CB
⇒GA= 4(5)-3= 17
hope it helps...
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