Answer:
73:120 change 2 hours into minutes which is 120
Notice that

so on the left side, a factor of <em>x</em> - 7 in the numerator and denominator can cancel

But we can only cancel them out as long as <em>x</em> ≠ 7 (because otherwise we'd have the indeterminate form 0/0 on the left side).
So, the equation is true for all <em>x</em> <u>except</u> <em>x</em> = 7. In set notation,

In interval notation,

Equation: <span>3b+4b^2-a^3
Given: </span><span>a=3 & b=-5
Plug 3 in for (a) and -5 in for (b):
</span><span>3(-5)+4(-5)^2-(3)^3
</span>
Now follow PEMDAS:
<span>3(-5) + 4(-5)^2 - (3)^3
</span>-15 + 4(-5)^2 - (3)^3
-15 + 100 - (3)^3
-15 + 100 - 27
85 - 27
58
the asnwer is 58.