Answer:
(x + 9)(x - 8)
Step-by-step explanation:
f(x) = x^2 + x - 72
= x^2 - 8x + 9x - 72
= (x^2 - 8x) + (9x - 72)
= x(x - 8) + 9(x - 8)
= (x + 9)(x - 8)
I don't know what the "six-step method" is supposed to be, so I'll just demonstrate the typical method for this problem.
Let <em>x</em> be the amount (in gal) of the 50% antifreeze solution that is required. The new solution will then have a total volume of (<em>x</em> + 60) gal.
Each gal of the 50% solution used contributes 0.5 gal of antifreeze. Similarly, each gal of the 30% solution contributes 0.3 gal of antifreeze. So the new solution will contain (0.5 <em>x</em> + 0.3 * 60) gal = (0.5 <em>x</em> + 18) gal of antifreeze.
We want the concentration of antifreeze to be 40% in the new solution, so we need to have
(0.5 <em>x</em> + 18) / (<em>x</em> + 60) = 0.4
Solve for <em>x</em> :
0.5 <em>x</em> + 18 = 0.4 (<em>x</em> + 60)
0.5 <em>x</em> + 18 = 0.4 <em>x</em> + 24
0.5 <em>x</em> - 0.4 <em>x</em> = 24 - 18
0.1 <em>x</em> = 6
<em>x</em> = 6/0.1 = 60 gal
Answer:
x = 1
Step-by-step explanation:
We need to solve for x by isolating the variable.
First, expand the parentheses:
2(x + 1) = 4
2 * x + 2 * 1 = 4
2x + 2 = 4
Then subtract by 2:
2x + 2 - 2 = 4 - 2
2x = 2
Finally, divide by 2:
2x/2 = 2/2
x = 1
Thus, x = 1.
Hope this helps!
Answer:
12.3 mph
Step-by-step explanation:
17.9 - 5.6 = 12.3
Answer:
each taco is $7.
Step-by-step explanation:
In total he spent $36. He bought a shirt for $22 and a bottle of water for $4.
22+4= 26
36-22= 14
14 divided by 2= 7
