Answer:
a = 2
Step-by-step explanation:
19= 7a +5
19-5=7a
14÷7=a
a=2
Answer:
15 miles
Step-by-step explanation:
Let's say the dock is at the origin on a coordinate plane and each unit is 1 mile. If the boat travels 9 mile due north, that means that we move up from the origin (0, 0) 9 units to point A (0, 9). Now, this boat moves 12 miles due west, so we will go 12 units to the left of (0, 9) to point B (-12, 9). See the attached drawing (sorry for the crudeness).
Notice that this is a right triangle with legs of 9 and 12. That means the distance from the boat to the dock is just the hypotenuse, so use the Pythagorean Theorem: distance = 
Thus, the answer is 15 miles.
Hope this helps!
Answer:
20.2
Step-by-step explanation:
181.1 divided by the amount of days Susie ran.
Answer:
2/9 and 7/4(or 1 3/4)
Step-by-step explanation:
A reciprocal is just the original number flipped.
"Will is twice as old as Jill."
Jill's age . . . . . J
Will's age . . . . 2J .
"Three years ago . . .
Jill's age then . . . . . J - 3
Will's age then . . . . 2J - 3
". . . Jill's age then was 2/5 of Will's age then."
J - 3 = (2/5) (2J - 3)
Multiply
each side by 5 : 5J - 15 = 2 (2J - 3)
Divide
each side by 2 : 2.5 J - 7.5 = 2J - 3
Subtract 2J
from each side: 0.5 J - 7.5 = -3
Add 7.5
to each side: 0.5 J = 4.5
Multiply
each side by 2 : J = 9
Jill is 9 y.o. now.
Will is 18 y.o. now.