She acciddently put two negative 468's
For substitution the answer is -3t+x-z=8. Hope I helped!
Remark
The easiest way to do this is to set up a proportion. But be careful how you do it.
Call the distance d
1/2 d / 3/5 hour = x * d / 1 hour
Divide both sides by d
1/2 // 3/5 = x / 1 Cross multiply
1/2 * 1 = 3/5 x divide by 3/5

Invert the bottom fraction and multiply.
The answer is 5/6 of the distance will be covered in 1 hour.
A real world situatiom is when you need to put bricks around a garden
Hello!
When adding matrices you add the numbers that are in the same position
1 + 4 = 5
0 + 1 = 1
3 + 7 = 10
The answer is (5 1 10)
Hope this helps!