Answer:
x = -5 and y = 3
Step-by-step explanation:
There are two equations :
3x − 2y = −21 ....(1)
2x + 5y = 5 ......(2)
Multiply equation (1) by 2 and equation (2) by 3.
6x - 4y = -42 ...(3)
6x + 15y = 15 ....(4)
Subtract equation (4) from (3) :
6x - 4y - (6x + 15y) = -42 -15
-4y -15y = -57
-19y = -57
y = 3
Put y = 3 in equation (2) :
2x + 5(3) = 5
2x = 5-15
2x = -10
x = -5
So, the value of x is (-5) and y = 3.
Answer:
You must mix 2.67 gals. of pure alcohol to obtain the desired mixture.
26.18 divided by 77 = 0.34. Therefore the percentage change = 66%
Do the division
(5.685 * 10^26) / (3.302*10^23)
= 1.722 * 10^3
or 1722 times greater
