Answer:
54.2 mph
Step-by-step explanation:
Since the drivers leave at the same time and travel in directions 90° from each other, their separation speed can be found using the Pythagorean theorem. Let c represent Cynthia's average speed. Then (c-10) will represent Tim's average speed. Their combined separation speed is 70 miles per hour, so we can write ...
70² = c² +(c -10)²
4900 = 2c² -20c +100 . . . . eliminate parentheses
c² -10c -2400 = 0 . . . . . . . . divide by 2; put in standard form
(c -5)² -2425 = 0 . . . . . . . . . rearrange to vertex form
c = 5 ±5√97 . . . . . . . . . . . . solve for c, simplify radical
c ≈ 54.244 ≈ 54.2 . . . . . . . use the positive solution
Cynthia's average speed was 54.2 miles per hour.
Answer:
3rd one is no. the others are all yes
Answer:
9.01 maybe my math might be wrong
Step-by-step explanation:
Answer:
X=20 degree
Step-by-step explanation:
∆A+∆D+∆O=180
2x+10+2x+90=180
collect like terms
2x+2x=180-100
4x=80
(4x)/4=(80)/4
x=20 degree
Multiply her answer by -6 and see if the result is -108
