Answer:
value of k = 6
Step-by-step explanation:
sum of all angles forming a straight line = 180°
so,
- 7k + 8 + 90 + 40 = 180
- 7k + 138 = 180
- 7k = 180 - 138
- 7k = 42
- k = 42/7
- k = 6
hence the value of k = 6
1.) y+6=3(x+2) C
y+6=3x+6
y=3x+6-6
y=3x+6
2.) y=1/2(x+8)-2 B
y=1/2x+4-2
y=1/2x+2
3.) y+1=1(x-3) E
y+1=x-3
y=x-3-1
y=x-4
4.) -4x+y=-2 A
y=-4x-2
5.) 2x-4y=-4 F
-4y=-2x-4
y=-2/-4x-4/-4
y=2/4x+4/4
y=1/2x+1
6.) 2x+4y=8 D
4y=-2x+8
y=-2/4x+8/4
y=-1/2x+4/2
y=-1/2x+2
<span>To find 7% tax on $9.79 multiply by 0.07 getting 0.6853
Then add 9.79 to 0.6853 getting 10.4753 (round to $10.48) </span>
Step-by-step explanation:
We have got the lines :

Both lines intercept the x-axis in the point :

In all point from x-axis the y-component is equal to 0.

We replace the I point in the lines equations:

From the first equation :

From the second equation :

Then 
Finally :

y = ax + b and y = cx + d have the same x-intercept ⇔ad=bc