<span>x^2 + 8x = -3
</span><span>x^2 + 8x + 16 = -3 + 16
using a^2 + 2 a b + b^2 = (a+b)^2
</span><span>
</span>x^2 + 8x + 16 = 13
<span>(x +4)^2 = 13
answer : 16 is the number </span><span>you must add to complete the square</span>
2000 is 1000 times larger than 2
A=(v-u)/t
We know a=2.5, v=40, u=10, so:
2.5=(40-10)/t
2.5t=40-10
2.5t=30
Divide both sides by 2.5
t=12 It takes 12 seconds for the car to reach 40m/s
To find out how far it went, you do:
d=v+1/2 at^2
d=10+1/2(2.5)(12)^2
d=10+1/2(2.5)(144)
d=10+(1.25)(72)
d=10+90
d=100m
Hope this helps :)
