Answer:
x = 4.5
y = -5
Step-by-step explanation:
2x - 3y = 24 2x + y = 4
y = -2x + 4
2x - 3(-2x + 4) = 24 y = -2(4.5) + 4
2x - (-6x + 12) = 24 y = -9 + 4
2x + 6x - 12 = 24 y = -5
8x - 12 = 24
8x = 36
x = 4.5
Mixed numbers are a mix of a whole number and a fraction
a easy one is
1 and 1/4+1 and 3/4
1 and 1/2 +1 and 1/2
1 and 9/10 and 1 and 1/10
etc
Equation 1) -x - y - z = -8
Equation 2) -4x + 4y + 5z = 7
Equation 3) 2x + 2z = 4
Solving for three variables is quite similar to solving for two variables. Just like when solving for two variables, you look for like variables & solve them one-by-one. So, let's get started! :)
Multiply ALL of equation 1 by four.
1) 4(-x - y - z = -8)
Simplify.
1) -4x - 4y - 4z = -32
Both equations 1 & 2 have the same three variables (x, y, z), so, we must look at these equations together.
1) -4x - 4y - 4z = -32
2) -4x + 4y + 5z = 7
Add these equations together, and create a fourth equation.
4) -8x - z = -25
Now, notice how both equations 3 & 4 have the same two variables (x, z).
So, we must look at these equations together.
3) 2x + 2z = 4
4) -8x - z = -25
Multiply ALL of equation 4 by 2.
4) 2(-8x - z = -25)
Simplify.
4) -16x - 2z =-50
3) 2x + 2z = 4
Now, add the equations together, so that we can solve for x.
-14x = -42
Divide both sides by -14.
x = 3
Now, plug in 3 for x into our 3rd equation.
3) 2x + 2z = 4
3) 2(3) + 2z = 4
Simplify.
6 + 2z = 4
Subtract 6 from both sides.
2z = 4 - 6
Simplify.
2z = -2
Divide both sides by 2.
z = -1
Now, plug in -1 for z & 3 for x in our 1st equation.
1) -x - y - z = -8
-(3) - y - (-1) = -8
Simplify.
-3 - y + 1 = -8
Simplify.
-2 - y = -8
Add 2 to both sides.
-y = -8 + 2
Simplify.
-y = -6
Divide both sides by -1.
y = 6
SO :
x = 3, y = 6, z = -1
~Hope I helped!~
A²+b²=c²
39²+b²=89²
1521+b²=7921
subtract 1521 from both sides
b²=6400
so then you square both sides
√6400
80
