Answer:
I'm sorry I don't know the equation, but she walks 3 mph.
Step-by-step explanation:
We know that the answer is asking for speed, which needs both distance and time, so we also need both. Which is where the 9 mph is used. 9 mph means its a difference. b means biking mph, w means walking mph, sooo ----->>> b=w+9, and the difference in the 1st equation is 36, which means the first equation is 4 times larger than the b=w+9, so she walked 48 miles, as well as walked 12 miles in 4 hours. Divide then distances by 4, and you get 12 miles and 3 miles in one hour. Or 12 mph & 3 mph, which fits into 12=3+9. So she walks 3 miles per hour.
4x+2y i hope that helps :3
First thing you should do is reduce coefficients.
1st equation has all multiples of '2'. Divide by 2
---> x +3y = -6
2nd equation has multiples of 5. Divide by 5.
---> x - y = 2
Now elimination part is easier.
Eliminate 'x' variable by subtracting 2nd equation from 1st.
x + 3y = -6
-(x - y = 2)
----------------------
4y = -8
Solve for 'y'
4y = -8
y = (-8)/4 = -2
Substitute value for 'y' back into 2nd equation:
x - (-2) = 2
x + 2 = 2
x = 0
Solution to system is:
x=0, y =-2
The answer is C
Hopes this helps
Answer:
y=30
Step-by-step explanation:
y-8=22
Add 8 on both sides
y=30