Well if you're wanting to use substitution, you first have to end up with one term on either side of the equation. Use the second one as it's easiest.
So: x-2y=11, so find -2y as there is a -2y in the first equation.
then that becomes -2y=11-x. then sub that into equation 1, and you get:
-x+11-x=-13, which equals to -2x+11=-13, which is -2x=-24, so therefore
x=12. then chuck the x into any of the equations to find what y equals.
hope this helps!
11. 8/7
14. 13/10
17. 11/14
We can subtract t from both sides to get...
x+t = 3.45
x+t-t = 3.45-t
x = 3.45-t
174 is equal to 174 if thats what the last one means
Note: 1 inch = 2.54 cm is an exact converion, while 1 mile=1.6km is only approximate.
Using conversion
1 inch=2.54 cm
1 mile = 1760*3*12 = 63360 in = 160934.4 cm
If 1 inch = 1 mile, then
2.54 cm : 1 mile = 1.609344 km
1 cm : 0.6336 km (exactly), or
1 cm : 0.6 km (approximately)
Using both conversions:
1 inch = 2.54 cm : 1 mile = 1.6 km
=>
2.54 cm : 1.6 km
1 cm : 1.6/2.54=0.6299 km (approximately), or
1 cm : 0.6 km (approximately)
