We can't eliminate as is so we have to change something up there in the equations to get either the x values the same number but opposite signs, or the y values the same number but opposite signs. I chose to change the y values to the same number but different signs. In the first equation y is -3y and in the second one, y is -8y. The LCM of both of those numbers is 24, so we will multiply the first equation by an 8 (8*3=24) and the second equation by 3 (3*8=24) but since they are both negative right now, one of those multiplications has to involve a negative because - * - = +. Set it up like this:
8(-10x - 3y = -18)
-3(-7x - 8y = 11)
Multiply both of those all the way through to get new equations:
-80x - 24y = -144
21x +24y = -33
Now the y's cancel each other out leaving only the x's:
-59x = -177 and x = 3. Now plug that 3 into either one of the original equations to find the y value. Either equation will work; you'll get the same answer using either one. Promise. -7(3) - 8y = 11 gives a y value of -4. so your solution is (3, -4) or B above.
Volume = Length x Width x Height
Volume = 80 x 45 x 12
Volume = 43200 ft³
Cost per cubic foot = $625 000 ÷ 43200
Cost per cubic foot = $14.47
----------------------------------------------
Answer: $14.47 per cubic foot.
----------------------------------------------
A.
For 12 - 1,
82 - 78 = 4 degrees per hour
For 1 - 3:15,
(88 - 82) / 2.25 = 2.67 degrees per hour
For 3:15 - 4:30,
(93 - 88) / 1.25 = 4 degrees per hour
For 4:30 to 6,
(91 - 93) / 1.5 = 1.33 degrees per hour
The time intervals 12 to 1 and 3:15 to 4 had the fastest rate of change
It is 70
i cant explain it right now i have work to do so sorry:)
