SOLUTION: Would someone please help me? I am absolutely desparate and stuck on these two problems. I would appreciate any help I can get. Thanks Solve by the elimination method 5r-6s=4

Algebra.Com
Question 342122: Would someone please help me? I am absolutely desparate and stuck on these two problems. I would appreciate any help I can get. Thanks
Solve by the elimination method
5r-6s=4
6r+5s=17
Solve by the substitution method
6x+7y=8
x=16-3y

Answer by ankor@dixie-net.com(22740)   (Show Source): You can put this solution on YOUR website!
Solve by the elimination method
5r-6s=4
6r+5s=17
We want to multiply one or both equations with values that will make the coefficient of one of the variables the same
In this system multiply the 1st equation by 5 and the 2nd equation by 6, we have:
25r - 30s = 20
36r + 30s = 102
-----------------Adding these eliminates s, find r
61r + 0 = 122
r =
r = 2
Use the original 2nd equation to find s, replace r with 2
6(2) + 5s = 17
12 + 5s = 17
5s = 17 - 12
5s = 5
s = 1
:
Check solution by replacing r and s in the 1st original equation
5(2) - 6(1) = 4
10 - 6 = 4; confirms our solution of r=2, s=1
:
:
Solve by the substitution method
Here we use one of the equation to substitute in the other equation
6x+7y=8
x=16-3y
We know that x = 16-3y, substitute (16-3y) for x in the 1st equation
6(16-3y) + 7y = 8
96 - 18y + 7y = 8
-18y + 7y = 8 - 96
-11y = -88
11y = 88; multiplied both sides by -1
y =
y = 8
;
Find x using the 2nd equation, replace y with 8:
x = 16 - 3(8)
x = 16 - 24
x = -8
:
Check solution in the 1st equation replacing x and y
6(-8) + 7(8) = 8
-48 + 56 = 8; confirms our solution of x=-8, y=8
;
:
Did this help you understand and relieve some of your desperation?
If not, try printing these examples out and study each step.
We want you to succeed in this.

RELATED QUESTIONS

can someone please help me with these two problems i am stuck 5t^3-45t=0... (answered by Maths68)
I am a bit stuck on these few problems and I can't get any help....Someone please help... (answered by mananth)
hello i am stuck on the following problem 1/2y + 10 = 2y-2 i would appreciate any help... (answered by solver91311,unlockmath)
I have 2 math problems that I am stuck on. I would appreciate any help available. Thank... (answered by stanbon)
I am really stuggling in Elementary and Intermediate Algebra. Math does not come very... (answered by scott8148,jam123)
I need to solve this help solving these two problems, I am stuck I came up with x=2 for... (answered by nerdybill,mangopeeler07)
You run a ten-kilometer race in 45.5 minutes. Write an inequality for the time,t, of the... (answered by solver91311)
I am so confused and stuck on these types of problems: -9+20=19x-4-18x please help... (answered by checkley71,josmiceli)
I would really appreciate any help you could can give me regarding the two following... (answered by Earlsdon)