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:
x ≈ 1.4
Step-by-step explanation:
Using the sine ratio in the right triangle
sin50° =
=
=
( multiply both sides by 1.8 )
1.8 × sin50° = x , then
x ≈ 1.4 ( to the nearest tenth )
7/10 = x/12 which mean you need to multiply each side by 12 to find x. So the answer would be X= 8.4
Combine like terms in each member of an equation.
Using the addition or subtraction property, write the equation with all terms containing the unknown in one member and all terms not containing the unknown in the other.
Combine like terms in each member.
Use the multiplication property to remove fractions.