What you want to do is take one of the 2 equations and isolate one variable. you will then use the value that you find for the variable and plug it back into the other equation. here is how:
This would be easiest to do with the second equation in the set since the x is not being multiplied by anything. So lets isolate the x in the second equation.
add 0.9y to both sides and you get:
x=4.5+0.9y
we now know what x is equal to in terms of y. so lets replace the x in the first equation with the new value. You get:
1.5(4.5+0.9y)-1.9y=-29
Now just solve for y:
6.75+1.35y-1.9y=-29
1.35y-1.9y=-35.75
-0.55y=-35.75
y=65
so now you know that y=65 so plug 65 in as y in the second equation to find x
x-0.9*65=4.5
Now simply solve for x
x-(-58.5)=4.5
x+58.5=4.5
x=-54
Hope this helped! :)
Answer:
361,240,062 X 201= [72609252462]
Step-by-step explanation:
They are essentially asking us to solve:

Solving this equation for x tells us that it will take around 80.1 years for the materials in the vault to reduce to 357 pounds.
Look in the table at the column that has 1 minute and 4.25 pages. Printer A prints 4.25 pages in 1 minute which is a rate of 4.25 pages per minute. The rate of printing is the slope in the equation. A rate of 4.25 pages per minute is represented by the equation y = 4.25x, where 4.25 ids the slope of the equation.
We are told that Printer A prints faster than Printer B, so Printer B must have a lower rate of printing than Printer A. The equation for Printer B must have a slope less than 4.25.
There are two choices which have a slope less than than 4.25.
Answer: y = 4.2x; y = 4x
the error is that they didnt add the exponets