Answer:
102 gallons of 55% antifreeze
68 gallons of 80% antifreeze
Step-by-step explanation:
55% antifreeze: x
80% antifreeze: y
x + y = 170 ===> -.55(x + y = 170) ===> -.55x - .55y = -93.5
.55x + .80y = .65(170) ===> .55x + .80y = 110.5
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add the two equations to eliminate a variable: 0.25y = 17
divide by 0.25 to isolate y: y = 68
substitution to find x:
x + y = 170
x + 68 = 170
x = 102
answer:
36
explanation to answer:
∠ e = 40°
Since Δ ABC and Δ EDC are congruent then corresponding angles are congruent, that is
∠ A = ∠ E = 40°