Answer:
Ava is 26 and Grace age is 9
Step-by-step explanation:
x=ava's age
y=grace's age
3y-1=x
x+y=35
Substitute 3y-1 to x+y=35 for the value of x to find grace age
3y-1+y=35
4y-1=35
+1 +1
4y=36
y=9 now substitute 9, the y value in 3y-1=x to find ava's age
3(9)-1=x
x=26
to verify; 26+9=35
true 35=35
Answer:
262.25 inches
Step-by-step explanation:
65% of 165 is 107.25
107.25+165=272.25
so the truck is 262.25 inches long
Both are correct.
Good job!
Answer: Height = 20 inches
Width = 14 inches
Step-by-step explanation:
The aquarium is rectangular. The formula for determining the volume of a rectangular box is expressed as
Volume = LWH
Where L,W and H represents the length, width and height of the box.
The aquarium holding African cichlids is 6 inches higher than it is wide. It means that
H = W + 6
Its length is 33 inches, and its volume is 9240 cubic inches. It means that
9240 = 33W(W + 6)
9240/33 = W(W + 6)
280 = W² + 6W
W² + 6W + (6/2)² = 280 + (6/2)²
(W + 3)² = 280 + 9 = 289
Taking square root of both sides, it becomes
W + 3 = √289 = 17
W = 17 - 3
W = 14
H = W + 6 = 14 + 6
H = 20
Answer:
x = 387
Step-by-step explanation:
The wind acts in the opposite direction to the plane when the time is longer.
The wind acts in the same direction as the plane when the time is shorter.
Equation
d = r*t
Givens
- d = 1720
- x = plane's speed
- y = wind speed
- t1 = 5 hours
- t2 = 4 hours.
Substitution
- d = (x + y) * t
- 1720 = (x + y) * 4
- 1720 = (x - y) * 5
Since the two distances are the same, you can equate the right hand sides.
- (x + y) * 4 = (x - y)*5 Remove the brackets.
- 4x + 4y = 5x - 5y Add 5y to both sides
- 4x + 4y + 5y = 5x - 5y + 5y Combine all the terms.
- 4x + 9y = 5x Subtract 4x from both sides
- 9y + 4x - 4x = 5x - 4x Combine
- 9y = x
Now use one of the given equations with the distance
- 1720 = (x + y)*4 Substitute 9y for x
- 1720 = (9y + y) * 4 Combine
- 1720 = 10y * 4 Multiply the right
- 1720 = 40y Divide by 40
- 1720/40 = 40y/40 Do the division
- 43 = y y = wind speek
- 9y = x x = 9*y
- 9*43 = x
- x = 387 miles per hour.
