For lesson 4 10^15/10^4= 10^11 because when you are dividing with exponents you have to subtract the bottom exponent with the top one so 15-4=11; 10^15/10^4=10^11
1.7 times 10 to the 9 power
1.52 times10 to the 8 power
The clues translate to
n/d = 2/3
(n+2)/(d+2) = 3/4
Solving this by cross multiplying both:
3n = 2d
3(d+2) = 4(n+2) => 3d + 6 = 4n + 8
then substituting d = 3/2 n in the second:
9/2n - 4n = 2 => 1/2 n = 2 => n = 4
if n=4 then d = 3/2*4 = 6.
So the original fraction was 4/6
The answer is :
y = 2x - 4