No she doesn't have enough money. All you do is multiply 8.60 by .2 which come out to 1.72 and 8.60 plus 1.73 which equals 10.33 so she needs 33 more cents tone able to tip 20%.
Answer:
(arranged from top to bottom)
System #3, where x=6
System #1, where x=4
System #7, where x=3
System #5, where x=2
System #2, where x=1
Step-by-step explanation:
System #1: x=4

To solve, start by isolating your first equation for y.

Now, plug this value of y into your second equation.

System #2: x=1

Isolate your second equation for y.

Plug this value of y into your first equation.

System #3: x=6

Isolate your first equation for y.

Plug this value of y into your second equation.

System #4: all real numbers (not included in your diagram)

Plug your value of y into your second equation.

<em>all real numbers are solutions</em>
System #5: x=2

Isolate your second equation for y.

Plug in your value of y to your first equation.

System #6: no solution (not included in your diagram)

Isolate your first equation for y.

Plug your value of y into your second equation.

<em>no solution</em>
System #7: x=3

Plug your value of y into your second equation.

Sine squared x + cos squared x is equal to 1