(4x + 3y)(4x − 3y) = (4x)^2 -12xy + 12xy - (3y)^2 =
16x^2 - 9y^2
Nearest hundredth: 3.96
Nearest ones: 4
<span>Question No.2
</span>
speed= distance/ time
1200km/0.006s= 200 000 km/s
<span>Question 4
</span>
wavelength = wavespeed / frequency
wavespeed = 16/8 = 2
Question 5
(400/60s) = 6.6667 waves/ sec (Hz).
<span>Velocity = 0.008m/sec. </span>
<span>Wavelength = (v/f) = 0.008/6.6667 = 0.0012 metre (1.2mm).
</span>
Well super easy 16 kil. per hour
Positive. Two negatives make a positive. I hope this helps :)
