Answer:
$20 i think
Step-by-step explanation:
Answer: -1 and 5.
Step-by-step explanation:
x - 4x = 5 : Move the constant to the left.
x^2 - 4x - 5 = 0 : Rewrite the expression.
x^2 + x - 5x - 5 = 0 : Factor the expressions.
x(x+1) - 5(x+1) = 0 : Factor the expression.
(x+1)(x-5) = 0 : Seperate into possible cases.
x + 1 = 0, x - 5 = 0 : Solve the equations.
x = -1, x = 5 : The equation has 2 solutions.
D. 4.25 < 43/10 < 13/3
4.25 = 4.25
43/10 = 4.3
13/3 = 4.33
4.25 < 4.3 < 4.33
Let
x--------> <span>the speed of the boat in mph
we know that
</span>going upstream the speed is x-7
<span>going downstream the speed is x+7
</span>
let the distance be d
<span>time to go upstream = d/(x-7) </span>
<span>time to go downstream = d/(x+7)
</span>
time going upstream is 3 times going downstream
so
<span>3d/(x+7) = d/(x-7) </span>
<span>divide by d </span>
<span>3/(x+7) = 1/(x-7) </span>
<span>3x-21 = x+7 </span>
<span>2x = 28 </span>
<span>x = 14
</span>
the answer is
<span>the speed of the boat in still water is 14 mph</span>
