for these you need to rearrange the equations and do substitutions.
#3 = if x+y=5 then you know x = 5-y
now substitute that equation for x in the 2nd one so x + 2y = 8 becomes
5-y + 2y = 8 2y - y becomes 1y which becomes y then subtract 5 from each side to get y =3
now replace y with 3 in the first equation x = 5-3 so x = 2
so (2,3) is the answer
same type of work for #4
2x-y=6 ,S0 y = 2X+6
so now you have 4x+2(2x+6)=-4
that becomes 4x +4x+12 = -4
8x+8 = 1, x =1
y = 2(1)-6 = -4
so answer is (1,-4)
Answer: x is 9, g is 41 and f is 6
Step-by-step explanation:
The answer should be b) division because you are dividing three from both sides to get x by itself
Answer:
2 1/3 hours or 2 hours 20 minutes.
51.4 mph to 1 decimal place.
Step-by-step explanation:
Time = distance speed
First 50 miles time taken = 50 / 60 = 5/6 hours
Second 50 miles - time = 50/40 = 5/4 hours.
Final 20 miles - time taken = 20 / 80 = 1/4 hours.
Total time taken = 5/6 + 5/4 + 1/4
= 5/6 + 6/4
= 10/12 + 18/12
= 28/12
= 7/3 or 2 1/3 hours or 2 hours 20 minutes.
Average speed = total distance / total time
= 120 / 7/3
= 120 * 3/7
= 51.4 mph to 1 decimal place.
Answer:
19 km east
Step-by-step explanation:
By going North 12 then south 12 the two cancel eachother out leaving only the eastern movement