Use Subtraction
1. Subtract
x+2y=7
3x-2y=-3
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4x+0y=4 SIMPLIFY 4x=4
2. DIVIDE
4x=4
x=1
Substitute that into either of the original equations to get x=1, y=3
B. 90. The perimeter is 30+30+15+15=90
Answer: 12.5 CC
Step-by-step explanation:
V=1/3Bh where B is the area of the base and h is the height
The perimeter of the square base is 8.6 so each side is 2.15 and the area of the base is (2.15)^2 or 4.6225
V=1/3(4.6225)(8.1)=12.5cc
Answer:
The completed reaction is
CaCO3 + 2 HCl → (Ca+2 + 2 Cl-)aq + H2O + CO2↑
15.7 feet
and you are welcome