Let x be the time she ran and y be the time she walked
then distance ran = 25x and distance walked = 5y
so 15x + 5y = 42
and x + y = 4
* second equn. by -5:-
-5x - 5y = -20
add this to the first equn:0
10x = 22
x = 2.2
distance she ran = 2.2 * 15 = 33 km
8^2 is 64 and 8^7 is 2097152 and do 64*2097152 which is 134217728.
as the world caves in :)
step by step explanation:
3x + 12 = 3
(multiply 3 by the variables in the parentheses)
3x + 12 = 3
add 12 to each side
3x = 15
divide each side by 3
X=5
