Answer:
x = -4
Step-by-step explanation:
To make this easier to explain and easier to solve, we're going to first multiply the second equation of 9x-7y=-15 by -1 to make the y coefficient positive.
This results in -9x+7y=15.
When we line up the two equations on top of each other now, we'll see that both the first and second equations have opposite y coefficients, which is vital for elimination.
The next step is to add the second equation to the first one. Teachers may tell you to subtract, but I find it easier to add if you make the two y coefficients of negative value to each other.
4x-7y=5
+ -9x+7y=15
___________
-5x+0y=20, or just -5x=20, because you have successfully eliminated the y variable.
From there, you're going to solve like a normal equation (divide both sides by -5) toget you x=-4.
A=90 degrees divide by 5
=18 degrees
2c+a=90
2c+18=90
2c=90-18
2c=72
divide each side by 2
c=36
therefore:
2c=72
b=4a+c
b=4(18)+36
b=72+36
b=108
400 Hamburgers
600 Hot dogs
Divide 2,400 by two because that's how many items they sold. You'll get 1,200.
Divide 1,200 by 3 because that's how much a hamburger costs and you'll end up with 400
Divide 1,200 by 2 because that's how much a hot dog costs and you'l end up with 600
To check, multiply 400x3 and 600x2
Then add the sums together- 1,200+1,200= 2,400
378 cm Is the correct answer i believe
