Answer:
3x - y = -7
Step-by-step explanation:
y = mx + b
m = deltay/deltax
m = (10 - 1)/[( 1 - (-2)]
m = 9/3 = 3
y = 3x + b
From (-2 | 1) we see that when x = -2, y = 1
Placing into the equation, in order to find b (y-intercept)
y = 3x + b
1 = 3(-2) + b
b = 7
y = 3x + 7 or 3x - y = -7
Answer:
X+20=2 i think this is a little above my head
Simplifying
25x + -15 = 2y
Reorder the terms:
-15 + 25x = 2y
Solving
-15 + 25x = 2y
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '15' to each side of the equation.
-15 + 15 + 25x = 15 + 2y
Combine like terms: -15 + 15 = 0
0 + 25x = 15 + 2y
25x = 15 + 2y
Divide each side by '25'.
x = 0.6 + 0.08y
Simplifying
x = 0.6 + 0.08y
Remark
There is no short way to do this problem and no obvious way to get the answer other that to solve each part.
Solve
A
Multiply by 2
x + 1.6 = 2(x + 0.1) Remove the brackets
x + 1.6 = 2x + 0.1*2
x + 1.6 = 2x + 0.2 Subtract x from both sides
1.6 = x + 0.2 Subtract 0.2 from both sides
1.6 - 0.2 = x
1.4 = x
Circle A
B
Subtract 2x from both sides.
3x - 2x = 1.4
Circle B
C
Remove the brackets.
4x + 6 = 2x - 6 Add 6 to both sides
4x + 12 = 2x Subtract 4x from both sides.
12 = -2x Divide by - 2
12/-2 = x
x = - 6 Don't circle C
D
I'm going to be very scant in my solution of this. You can fill in the steps.
3x = 4.2
x = 4.2/3
x = 1.4
Circle D
Given your ordered pair you would assume a = 5, b = 2
Set up both equations
5 + 2 = 7
7 = 7 (the numbers are equal so this correct)
2(5) - 8 = 2
10 - 8 = 2
2 = 2 (the numbers are equal so this is also correct)
Because both equations work with the ordered pair they <em>are</em><span> the solution of the given system.</span>