Answer: 3.675 seconds
Step-by-step explanation:
Hi, when the object hits the ground, h=0:
h=−16t^2+48.6t+37.5
0=−16t^2+48.6t+37.5
We have to apply the quadratic formula:
For: ax2+ bx + c
x =[ -b ± √b²-4ac] /2a
Replacing with the values given:
a=-16 ; b=48.6; c=37.5
x =[ -(48.6) ± √(-48.6)²-4(-16)37.5] /2(-16)
x = [ -48.6 ± √ 4,761.96] /-32
x = [ -48.6 ± 69] /-32
Positive:
x = [ -48.6 + 69] /-32 = -0.6375
Negative:
x = [ -48.6 - 69] /-32 = 3.675 seconds (seconds can't be negative)
Feel free to ask for more if needed or if you did not understand something.
12x - 8y = -12
6x + 4y = -30
Multiply the 2nd equation by 2, to make the Y coefficients opposite:
6x + 4y = -30 x 2 = 12x + 8y = -60
Now add the two equations:
12x -8y = -12 + 12x +8y = -60
= 24x = -72
Divide bothe sides by 24 to solve for x:
x = -72/24
x = -3
Now replace x with -3 in the first equation to solve for y:
12(-3) - 8y = -12
-36 - 8y = -12
Add 36 to each side:
-8y = 24
Divide both sides by -8 to solve for y:
y = 24 / -8
y = -3
X = -3 and y = -3
(-3,-3)
Answer:
9. 70° 10. 90° 11. 110°
Step-by-step explanation:
12. 25°
13. 95°
14. 20°
4a + 3 = 15
- 3
4a = 12
÷ 4
a = 3
I hope this helps!
No, ΔPʹQʹRʹ is a reflection of ΔPQR over the x-axis
