(1) The integral is straightforward; <em>x</em> ranges between two constants, and <em>y</em> ranges between two functions of <em>x</em> that don't intersect.

(2) First find where the two curves intersect:
<em>y</em> ² - 4 = -3<em>y</em>
<em>y</em> ² + 3<em>y</em> - 4 = 0
(<em>y</em> + 4) (<em>y</em> - 1) = 0
<em>y</em> = -4, <em>y</em> = 1 → <em>x</em> = 12, <em>x</em> = -3
That is, they intersect at the points (-3, 1) and (12, -4). Since <em>x</em> ranges between two explicit functions of <em>y</em>, you can capture the area with one integral if you integrate with respect to <em>x</em> first:

(3) No special tricks here, <em>x</em> is again bounded between two constants and <em>y</em> between two explicit functions of <em>x</em>.

The actions are that some people will or may not pay forthe gas if it costs that much!
Given that:
Lake Superior contains 3.0 x 10^15 gallons of water
Firstly, let's know that of 1 gallon;
1 gallon = 0.00375 cubic meter
Then, 3.0 x 10 ^15 = 3.0x10^15 x 3.785 x 10 ^-3
= 3 x 3.785 x 10^15-3
= 11.355 x 10 ^12m^3
Therefore, 11.355x10^12 cubic meters of water are contained in the lake.
Answer: x + 30 = 10 and x + 30 = –10
Explanation: The two equations can be used to find the minimum and maximum depths Laurie wants to stay between is the below:
x + 30 = 10 and x + 30 = -10
Hope this helps!