algebra

posted by .

solve the following simultaneous equations

5y=13
x+y/2+30=0

2x-2y=9
2x+2y=9

The first set, I have no idea and the second set I tried but wish to double check.

• algebra -

try to get x or y singled out in the easiest equation (or just pick)

fe for the first one : y = 13/5
fe for the second one : x = (2y+9)/2

then fill in that x or y in the other equation

fe for the first one : x+(13/5)/2 +30 = 0
fe for the second one : 2*((2y+9)/2) + 2y = 9

by this you have 1 equation with 1 unknown, calculate, once you get the final result for x or y, fill it in in the other equation to get y or x

glhf

Similar Questions

1. System of equations

3x =2y = 17 2x-y =9 and 3x+y = 3 x+2y = -4 How do I do these?
2. How do I do this.?(Math.)

Use the Substitution method to solve the system of equations. y - 2x = -5 3y - x = 5 Solve one of the equations for x or y. Let's solve the first one for y: y - 2x = -5 y = 2x - 5 Now let's substitute 2x - 5 for y in the second equation …
3. Engineering

I need help solving the following simultaneous equations, for the values of Vo and a: 1.4 = Vo e^-32a 4 = Vo e^-6a I've never come across simultaneous equations like this (e is the base of natural logarithms, so perhaps taking logs …
4. maths pls help

1. Solve the following simultaneous equations: log2 xy = 7 log2 (x^2/y) = 5 2. If log y x =a and log z x=b where x is not equal to 1, express the following in terms of a and b: logy (yz) Solve the following simultaneous equations: …
5. Math

I have tried this problem a few ways, and I am getting frustrating results. Could you help me out by showing me how to set the systems of equations Two angles are complementary The sum of the measure of the first angle and 1/4 the …
6. Math

I have tried this problem a few ways, and I am getting frustrating results. Could you help me out by showing me how to set the systems of equations Two angles are complementary The sum of the measure of the first angle and 1/4 the …
7. math

solve the simultaneous equations to find the coordinates of the point of intersection for the pair of lines of the simultaneous equations. Then check the answer by graphing the equations 3x-y=-4 2x-y=0
8. Math

As a restaurant owner there are many decisions that you need to make on a daily basis, such as where to keep inventory levels. You wish to replenish your stock of dishes by purchasing 250 sets for your restaurant. You have two dish …
9. algebra

1 Solve the set of linear equations by the matrix method : a+3b+2c=3 , 2a-b-3c= -8, 5a+2b+c=9. Sove for a 2 4 7 3 2 Solve the set of linear equations by Guassian elimination method : a+2b+3c=5, 3a-b+2c=8, 4a-6b-4c=-2. Find a 1 4 5 …