Answer:
x= 3
Step-by-step explanation:
1. -5(3) + 2 = -13
2. -15 + 2 = -13 <em>A positive times a negative will always equal a negative</em>
3. -13 = -13 <em>Whenever you add anything to a negative number, the </em>
<em> number becomes smaller </em>
Ex: -10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, ...........
<em>Although the number itself becomes smaller, its value </em>
<em> becomes bigger </em>
Hope this helps.
Answer:??????????????????
Step-by-step explanation:
I am going to explain this using the substitution method, considering it appears to be the best in this situation.
We know (from the bottom equation) that y can equal 3x+20. Using this knowledge, we substitute the y in the top equation for 3x+20. Now, we have an equation that looks like this:
3x+20=x^2+2x
Now we need to move x to one side and then do some radicals (square roots).
Subtract the 2x on the right (since it is smaller, negatives = NONONO), which will give you
x+20=x^2
Now, we take the square root of both sides to get
rad(x+20)=x
Now we have to simplify. 20 doesn't have a square root, but 4 goes into 20, and 4 has a square root of 2. This now becomes
2rad(x+5)
This doesn't simplify any further... we have a problem... no way to isolate x as far as my knowledge goes... Sorry, can't help you any further than that, but another person or your teacher might be able to. R.I.P...
Just use the Pythagorean Theorem
(9 +x)^2 = 15^2 + x^2
x^2 + 18x + 81 = 225 + x^2
18x = 144
x = 8
So the three sides of the triangle are
15, 8 and 17
The percent markup is 62.5%
The work is provided in the image attached.
