First one is 2 and last one is -1/3. Hope this helps :P
Downstream DATA:
distance = 12 miles
time = 2 hours
rate = 12/2 = 6 mph
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Upstream DATA:
distance = 12 miles
time = 4 hrs
rate = 12/4 = 3 mph
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Equations:
Downstream: b + c = 6
Upstream::: b - c = 3
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Add to get:
2b = 9
b = 4.5 mph (speed of the boat in still water.)
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Solve for "c":
b + c = 6
4.5 + c = 6
c = 1.5 mph (speed of the current)
The answer is 1.5 mph
X × x = x^2
x × -3 = -3x
3 × x = 3x
3 × -3 = -9
x^2 + 3x - 3x - 9
So I would agree with C because the -3x and the 3x cancel each other out. I hope this helps!
Answer:
1st option
Step-by-step explanation:
Given the 2 equations
2x + 5y = 19 → (1)
y = 3x - 3 → (2)
Substitute y = 3x - 3 into (1)
2x + 5(3x - 3) = 19
