Answer:
x = -5
y = -5
Step-by-step explanation:
If you multiply the top equation by negative 2, you can add it to the bottom equation and cancel out the x:
-2(-x + 5y = -20) --> 2x - 10y = 40
Add this to the bottom equation top to bottom:
2x - 10y = 40
-2x + 4y = -10
You get:
-6y = 30
Then solve for y:
y = -5
Plug this back in for either equation and solve for x:
-x + 5(-5) = -20
-x -25 = -20
-x = 5
x = -5
Your answers are:
x = -5
y = -5
Answer:
310
Step-by-step explanation:
total no.of students=1872
ratio of boys to girls=7:5
sum of ratio=total of students
12/12=1872
7/12=?
7/12*1872/1=1092which is the number of girls
1872-1092=780which is the number of boys
difference =1092-780= 310
Answer:
brainly.com
Step-by-step explanation:
sorry my bad copy paste error
Answer:
A Variable
Step-by-step explanation:
Variables are used to mark an unknown value. Common math problems ask you to solve for it.
For example in 5x+23=45, 'x' is the variable.
A constant is a number without a variable.
<em>Brainilest Appreciated. </em>
The correct answer would be at and t because its cheaper for 50 text