That is about right... 2,514 X 2 = 5,028 so he is about 1,000 off. I will leave the rest to you.
Answer:
-7/x
Step-by-step explanation:
first, you combine the terms together to get -7x^-1. you cant have negative exponents in the numerator so you move the x^-1 to the denominator. once it move its becomes positive then.
Answer:
-45
Step-by-step explanation:
5 *-1 *-3= 15
4 *-3 *4= -48
3 *4 *-1=-12
15 -48 -12= -45
Answer:
If you are solving the equation for x :
3x + 3y = 180
3x = -3y + 180
x = -y + 60 or x = 60 - y
If you are solving the equation for y:
3x + 3y = 180
3y = -3x + 180
y = -x + 60 or y = 60 - x
Try this:
1) note that weight of pure antifreeze before mixing and after mixing is the same. So, if 'x' is weight of pure antifreeze in 50% solution, it is possible to make up equation before mixing: 0.5x+0.2*90.
2) there are 0.2*90=18 gal. of pure antifreeze in the 20% solution. If 'x' gal. is the weight of pure antifreeze in 50% sol. and 18 gal. is the weight of pure antifreeze in 20% sol., it is possible to make up an equation after mixing: 0.4(x+18).
3) using the both parts: 0.5x+0.2*90=0.4(x+18) ⇒ x=54 gal. of <u>pure</u> weight.
4) to find 50% solution of 54 gal. pure weight just 54:0.5=108 gal.
Answer: 108 gal.