For 11, we can subtract x from both sides for the first equation to get y=8-x, making the slope -1 for both equations and therefore making it parallel.
For 13, we can solve for y in the first equation by subtracting 14 from both sides and therefore getting 2x-14=y. For the next one, we can subtract 4x from both sides to get 10-4x=2y. Dividing both sides by 2, we get 10-2x=y. Since for the equations to be parallel they must be the same and for perpendicular they must be -1/(slope), this fits neither.
Using those two explanations, I implore you to solve the other two on your own!
This doesn’t include the Einstein problem cause I didn’t have that one.
∠1 + ∠2 = 180°
⇒ 2x + 10x = 180°
⇒ 12x = 180°
⇒ x = 180°/12 = 15°
∠1 = 2x = 2×15° = 30°
His rate is 4.5 miles per hour. It would take him 4 hours to hike 18 miles. He would have traveled 31.5 miles in 7 hours.
En español por favor que no entiendo
