Answer:
14. x=-2.5, y = -7
15. x=28 y = -20
Step-by-step explanation:
14. Let's solve this system by elimination. Multiply the first equation by -1.
-1*(4x-y)= -1*(- 3)
-4x +y = 3
Then add this to the second equation.
-4x+y = 3
6x-y= - 8
--------------
2x = -5
Divide each side by 2
x = -2.5
We still need to find y
-4x+y =3
-4(-2.5) + y =3
10 +y =3
Subtract 10 from each side.
y = 3-10
y = -7
15.I will again use elimination to solve this system, because using substitution will give me fractions which are harder to work with. I will elimiate the y variable. Multiply the first equation by 11
11(
5x+6y)= 11*20
55x+66y = 220
Multiply the second equation by -6
-6(9x+11y)=32*(-6)
-54x-66y = -192
Add the modified equations together.
55x+66y = 220
-54x-66y = -192
---------------------------
x = 28
We still need to solve for y
5x+6y = 20
5*28 + 6y =20
140 + 6y = 20
Subtract 140 from each side
6y = -120
Divide by 6
y = -20
Answer:
368
Step-by-step explanation:
angle 1 = 180-110 = 70 degrees (linnear pair)
angle 2= 180-115 = 65 degrees (linnear pair)
angle 3 = angle 2 = 65 degrees (corresponding angles)
angle 4= 180 - angle 3 = 180-65 = 115 degrees (linnear pair)
(your teacher might not like this, depends on the cituation, but use 180 degrees in triangle to get 7)
angle 7 = 180 -angle1 -angle 2= 180-70-65= 45 degrees
angle 6 = angle 7 = 45 degrees ( vertical angles)
angle 8= 180- angle 7= 180-45 = 135 ( linnear pair)
angle 9 =angle 6 = 45 degrees (corresponding angles)
angle 5=angle 9=45 degrees (vertical angles)
