Okay so you take the 12 feet I'm pretty sure you multiply 12 and 30 and then that's one of your answers and then the 12 and a 75 you must put those to together and that's an answer and you subtract your 12 x 30 and you're 12 x 75 and that's how you get your answer I am pretty sure that's how you and that's how you get your answer I am pretty sure that's how you do it
First we need a point (x,y) : (A, 7)
<span>Now slope (from f'(A)) = 15 </span>
<span>Next, the equation (using point slope formula) </span>
<span>y - 7 = 15 (x -A) </span>
<span>y = 15 (x - A) + 7 </span>
<span>Now in the x spot we put 'A-.01' </span>
<span>y = 15 ( A - .01 - A) +7= 15(-.01) +7 = -.15+ 7 = 6.85
hope this helps</span>
2x+3 + 3x-4 + 2x+3 + 3x-4 = 78
10x -2 = 78
10x = 80
x=8
deck is 2(8)+3 by 3(8)-4, or 19 by 20