Suppose that equation of parabola is
y =ax² + bx + c
Since parabola passes through the point (2,−15) then
−15 = 4a + 2b + c
Since parabola passes through the point (-5,-29), then
−29 = 25a − 5b + c
Since parabola passes through the point (−3,−5), then
−5 = 9a − 3b + c
Thus, we obtained following system:
4a + 2b + c = −15
25a − 5b + c = −29
9a − 3b + c = −5
Solving it we get that
a = −2, b = −4, c = 1
Thus, equation of parabola is
y = −2x²− 4x + 1
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Rewriting in the form of
(x - h)² = 4p(y - k)
i) -2x² - 4x + 1 = y
ii) -3x² - 7x = y - 11
(-3x² and -7x are isolated)
iii) -3x² - 7x - 49/36 = y - 1 - 49/36
(Adding -49/36 to both sides to get perfect square on LHS)
iv) -3(x² + 7/3x + 49/36) = y - 3
(Taking out -3 common from LHS)
v) -3(x + 7/6)² = y - 445/36
vi) (x + 7/6)² = -⅓(y - 445/36)
(Shifting -⅓ to RHS)
vii) (x + 1)² = 4(-1/12)(y - 445/36)
(Rewriting in the form of 4(-1/12) ; This is 4p)
So, after rewriting the equation would be -
(x + 7/6)² = 4(-⅛)(y - 445/36)
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I hope this is what you wanted.
Regards,
Divyanka♪
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I think it's 7 1/2 because you can turn 30 1/4 to 15/2, which simplifies to 7 1/2
Answer:
S(t) = -4.9t^2 + Vot + 282.24
Step-by-step explanation:
Since the rocket is launched from the ground, So = 0 and S(t) = 0
Using s(t)=gt^2+v0t+s0 to get time t
Where g acceleration due to gravity = -4.9m/s^2. and
initial velocity = 39.2 m/a
0 = -4.9t2 + 39.2t
4.9t = 39.2
t = 8s
Substitute t in the model equation
S(t) = -49(8^2) + 3.92(8) + So
Let S(t) =0
0 = - 313.6 + 31.36 + So
So = 282.24m
The equation that can be used to model the height of the rocket after t seconds will be:
S(t) = -4.9t^2 + Vot + 282.24
1/6 = 0.16 with a line over the 6 because it is repeating
Answer:
20
Step-by-step explanation:
→ First find the value of x and y
x + y = 5
x - y = 4
→ Add the equations to cancel out the y's
2x = 9
→ Divide both sides by 2 to find the value of x
x = 4.5
→ Substitute x = 4.5 back into x - y = 4 to find the value of y
4.5 - y = 4
→ Minus 4.5 from both sides to isolate -y
-y = -0.5
→ Multiply everything by -1
y = 0.5
→ Substitute x = 4.5 and y = 0.5 into x² - y²
4.5² - 0.5² = 20.25 - 0.25 = 20
