Question

How do you do the bottom 4? Thanks!

Answer 1

Alrightie! So we are trying to isolate independent variables! WOO HOO! 

So for a.) y = mx + b which is the point-slope formula... do this :)

y = mx + b
y - b = mx + b - b
y - b = mx 

$\frac{y-b}{x} = \frac{mx}{x}$
$m = \frac{y-b}{x}$

b.) follow the same way I did above, but instead of dividing x, divide by m.

c.)  I = prt which is the equation for interest. 
divide each side by pr.

d.) This one is like a and b. So lemme show ya.

$A - p = prt$
$\frac{A-p}{pr} = \frac{t}{pr}$
$t = \frac{A-p}{pr}$