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...
From the looks of it, I believe it is either 120, 125, or 126. If you have options, let me know so I can take a closer look.
Answer:
1.29(30) +2
Step-by-step explanation:
First you do 1.29 times 30 that equals 38.7. Then you do 38.7 + 2 and you get 40.7. This means that the total cost is $40.70.
Answer: My answer was wrong sorry
Step-by-step explanation:
