Answer:
A & D
Step-by-step explanation:
The parabola opens up, so the minimum value of y is at the point (1, -2) and the graph passes thru the x-axis at 3 and -1, so those are the x-intercepts.
The axis of symmetry is x = 1, not y = -2 and the graph never has a maximum value. Parabolas that open up never have a maximum value.
Step-by-step explanation:
For a quadratic equation y = ax² + bx + c, the vertex (the maximum or minimum point) is at x = -b/(2a).
1) y = -0.5t² + 2t + 38
The maximum is at:
t = -2 / (2 × -0.5)
t = 2
The maximum height is:
y = -0.5(2)² + 2(2) + 38
y = 40
The coordinates of the vertex are (2, 40). That means the missile reaches a maximum height of 40 km after 2 minutes.
2) y = -4.9t² + 12t + 1.6
The maximum is at:
t = -12 / (2 × -4.9)
t = 1.22
The maximum height is:
y = -4.9(1.22)² + 12(1.22) + 1.6
y = 8.95
The coordinates of the vertex are (1.22, 8.95). That means the missile reaches a maximum height of 8.95 m after 1.22 seconds.
3) y = -0.04x² + 0.88x
The maximum is at:
x = -0.88 / (2 × -0.04)
x = 11
The maximum height is:
y = -0.04(11)² + 0.88(11)
y = 4.84
The maximum height of the tunnel is 4.84 meters.
The maximum width is when y = 0.
0 = -0.04x² + 0.88x
0 = -0.04x (x − 22)
x = 22
The maximum width is 22 feet.
Answer:
x = 27/10 or x = 2.7
Step-by-step explanation:
Step 1: Get rid of the denominator.
LCD of 4 & 3: 12
Multiply both sides by 12.
12 ( 2x - 1 / 4 ) + 12 ( x / 3 ) = 12 (2)
Reduce the numbers.
3 ( 2x - 1) + 4x = 24
Step 2: Distribute.
6x - 3 + 4x = 24
Step 3: Collect like terms.
6x + 4x = 24 + 3 ( - 3, the sign change when moved to the other side)
10x = 27
Step 4: Solve for x.
Multiply both sides by 10.
10x / 10 = 27 / 10 (the 10 cancels out)
x = 27 / 10 or x = 2.7
Answer: x = 27 / 10 or x = 2.7
Amy: (3 pages/min)(x min) + 9 pages
Sam: (2 pages/min)(x min) + 47 pages
Equate these: 3x+9 = 2x + 47
Then x = 38. The two friends will have covered the same number of pages after 38 minutes. How many pages would that be? 3(38)+9 = 123 pages.
Answer:
I think its 28 feet
Step-by-step explanation:
2x2=4
3x8=24
24+4=28 ft
