2x+4y=0
substitute y with 0
2x+4(0)=0
solve the equation
2x+0=0
2x=0
divide by 2 on both sides
x=0
4x+8y=7
substitute y with 0
4x+8(0)=7
solve the equation
4x+0=7
4x=7
divide by 4 on both sides
x=7/4 or x=1 3/4 or x=1.75
3x-7y=-29
2x+2y=6
solve the bottom equation
3x-7y=-29
x=3-y
substitute for x
3(3-y)-7y=-29
solve the equation
y=19/5
now substitute for y
x=3-
solve for x
x=-4/5
the possible solution of the system is the ordered pair
(x,y)=(
)
Answer:

Step-by-step explanation:
Slope Formula: 
Simply plug in 2 coordinates into the slope formula to find slope <em>m</em>:




Answer: 
Step-by-step explanation:
<u>Use trigonometry (shown in image below) to find the 3 side-lengths:</u>
- The side opposite of θ =

- The base side adjacent to θ = 11
- The hypotenuse = 12
<u>According to right triangle trigonometry:</u>
cos θ = 
<u>Substitute in the values:</u>
cos θ = 
Let x=grams of 70% alloy:
0.70x+16×0.20=0.30(x+16)
0.70x=0.30x+4.8-3.2
0.40x=1.6
x=1.6/0.4=16/4=4g
4 grams of 70% alloy are needed.
Sum of all angles is 360. There are 8 angles. 360/8 is 45. Exterior and interior angles are supplementary meaning their sum is 180. 180-45 is 135.