Answer:
paper clips = $1.85
index cards = $3.95
Step-by-step explanation:
Mark
12 paper clips = x
10 index cards = y
$61.70 total
Janice
15 paper clips = x
7 index cards = y
$55.40 total
12x + 10y = 61.70
15x + 7y = 55.40
*** you want to cancel out one of the letters
(12x + 10y = 61.70) * -7
(15x + 7y = 55.40) * 10
-84x -70y = -431.9
150x + 70y = 554.0
150x + 70y = 554.0
-84x -70y = -431.9
66x + 0 = 122.1
66x = 122.1
x = 122.1 ÷ 66
x = 1.85
plug it back in
15(1.85) + 7y = 55.40
27.75 + 7y = 55.40
7y = 55.40 - 27.75
7y = 27.65
y = 27.65 ÷ 7
y = 3.95
<h2>Answer:</h2><h2>15,005,015,972</h2><h2></h2><h2>Hope this helps!!</h2>
Answer:
X=1.2
Step-by-step explanation:
i just did that
Answer:
Hi There the correct answer is {x,y} = {-1,-10}
System of Linear Equations entered :
[1] 3x - y = 7
[2] 4x - 2y = 16
Graphic Representation of the Equations :
y + 3x = 7 -2y + 4x = 16
Solve by Substitution :
// Solve equation [1] for the variable y
[1] y = 3x - 7
// Plug this in for variable y in equation [2]
[2] 4x - 2•(3x-7) = 16
[2] -2x = 2
// Solve equation [2] for the variable x
[2] 2x = - 2
[2] x = - 1
// By now we know this much :
x = -1
y = 3x-7
// Use the x value to solve for y
y = 3(-1)-7 = -10
Solution :
{x,y} = {-1,-10}
Hope it helps!
