X-2.13=5.3 x= 5.3 + 2.13 x = 7.43
+2.13
Process:
Start by isolating the variable by itself, in this case we add 2.13 to the -2.13 as whatever we do to one side of the equation we do to the other hence we add 2.13 to 5.3 which will become x = 7.43 and we can verify our answer by substituting our answer for x
7.43 - 2.13 = 5.3
Answer
P+3
Step by step explanation
12+3=15
15 mi/h= 15mi/60 min= 1/4 (mi/min)
x is original speed (mi/min)
t is original time
x*t =260
(x+1/4)=5x/4 is new speed
t-20 - new time
(x+1/4)(t-20)=260
xt = (x+1/4)(t-20)
xt=xt + t/4 - 20x - 5
t/4=20x+5
t=80x +20
We can substitute t=80x +20 into equation x*t =260
x*(80x+20)=260
80x²+20x-260=0
4x²+x-13=0
D=b² - 4ac = 1+4*4*13= 209
x=(-1+/-√209)/2*4
x=1.68 mi/min
1.68mi/min * 60 min/1h≈100 mi/h
Check
260/100=2.6h time with old speed
260/(115)=2.26 h time with new speed
2.6-2.26 = 0.34 h difference between old and new time
0.34h*60min/1h≈20 min difference between old and new time in minutes
Answer: 5
Step-by-step explanation: add 5 on each side and you get -50 then divide -5/2 with -50 and get 5