Answer:
56
Step-by-step explanation:
Think of it this way, 7 times 10 is 70.
7*8 is 2 less 7s, or 14 less.
70-14=56
Or, a simpler way:
7*7 is 49(perfect square)
One more seven than that is 56.
These are just two ways I quikcly remember, because for some reason I struggle with 7 and 8 mulitplication.
Hope this helps!
if we take a look of the graph, let's notice that
AC = 4x + 4
AB = 14
BC = 3x - 4
now, AC = AB + BC,
![\bf AC=AB+BC\implies AC-BC=AB\implies \stackrel{AC}{(4x+4)}-\stackrel{BC}{(3x-4)}=\stackrel{AB}{14} \\\\\\ 4x+4-3x+4=14\implies x+8=14\implies x=6 \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ AC=4(6)+4\implies \boxed{AC=28}](https://tex.z-dn.net/?f=%5Cbf%20AC%3DAB%2BBC%5Cimplies%20AC-BC%3DAB%5Cimplies%20%5Cstackrel%7BAC%7D%7B%284x%2B4%29%7D-%5Cstackrel%7BBC%7D%7B%283x-4%29%7D%3D%5Cstackrel%7BAB%7D%7B14%7D%0A%5C%5C%5C%5C%5C%5C%0A4x%2B4-3x%2B4%3D14%5Cimplies%20x%2B8%3D14%5Cimplies%20x%3D6%0A%5C%5C%5C%5C%5B-0.35em%5D%0A%5Crule%7B34em%7D%7B0.25pt%7D%5C%5C%5C%5C%0AAC%3D4%286%29%2B4%5Cimplies%20%5Cboxed%7BAC%3D28%7D)
Answer:
x =4.5 hours
Step-by-step explanation:
We can use ratios to solve
150 miles 270 miles
--------------- = --------------
2.5 hours x miles
150 *x = 270*2.5
Divide each side by 150
150x/150 = 270*2.5/150
x =4.5 hours
