1/2* (DC) * (GF) + 1/2 * (GF) * (GF) = 80 (Given in the question statement).......(1)
DC-GF = 4 (from statement 2)
DC = 4+GF........(2)
From (1) and (2)
\(\frac{1}{2} (4+GF) *GF + \frac{1}{2} * (GF)^2 = 80\)
\((GF)^2 +2*GF - 80 = 0\)
We can stop here. Since the product of the roots are negative, we will get 1 positive root and 1 negative root. (As i mentioned in my previous solution, we're interested only in positive root)
Anyways,
\((GF)^2 +10GF -8GF -80 = 0\)
(GF+10)(GF-8) = 0
GF = -10 or 8
Side can't be negative. So, we discard -10.
GF= 8 and DC = 4+8=12
SiddharthR
nick1816
We need the length of the sides of the square.
Area of DBH = 1/2* (DC) * (GB) + 1/2 * (GF) * (GB) = 80
Area of DBH = 1/2* (DC) * (GF) + 1/2 * (GF) * (GF) = 80...... (1) [since GF = GB]
Statement 1. We know GF or GB. We can find DC using equation 1.
Sufficient
Statement 2- We know DC - GF. We have 2 equations and 2 variables. We can find DC and GF. [We are interested in +ve values]
Sufficient.
.
Could you solve statement II. I’m unable to see how that is sufficient
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