Answer: x= -20
Step-by-step explanation:
Add 85 85 to both sides.
-8x=2x+115+85−8x=2x+115+85
Simplify 2x+115+852x+115+85 to 2x+2002x+200.
-8x=2x+200−8x=2x+200
Subtract 2x2x from both sides.
-8x-2x=200−8x−2x=200
Simplify -8x-2x−8x−2x to -10x−10x.
-10x=200−10x=200
Divide both sides by -10−10.
x=-\frac{200}{10}x=−
10
200
Simplify \frac{200}{10}
10
200
to 20 20.
x= - 20
You cannot tell which number is greater just by the leftmost digits. This is because you do not know how many digits each number has. Ex: 80 and 3,000
Let the numbers be x and y, then
2x + y = 47 . . . (1)
x + 3y = 56 . . . (2)
(2) x 2 => 2x + 6y = 112 . . . (3)
(1) - (3) => -5y = -65 => y = -65/-5 = 13
From (2), x + 3(13) = 56 => x = 56 - 39 = 17
The two numbers are 13 and 17.
Answer:
500 phones
Step-by-step explanation:
cost of manufacturing: y = 80x + 10,000
money from phone sales: y = 100x
* note: x = #phones
solve for when they're equal;
100x = 80x + 10,000
100x - 80x = 80x - 80x + 10,000
20x = 10,000 –––––––––––> divide both sides by 20
x = 500
