13. You add the 8 and the 5
It's a simultaneous equation:
Steps:
1.Number the equations..
a+b=77 -1
a-b=13 -2
2. Choose what variable you want to use. In this case I would use the "b". Since the signs in front of the "b's" are different, add the two equations together
a + b = 77
+ + +
a (-b) = 13
Which gives;
2a = 90
Then solve to find a:
2a=90
a= 90/2
a=45
3.Then plug the "a" value into any of the original equations to find the "b" value. I would use equation 1 since the all the variables are positive.
a + b = 77
(45) + b = 77
b=77-45
b=32
4.Solution
a=45
b=32
Answer: B
Step-by-step explanation:
Answer:
10.8 gallons
Step-by-step explanation:
First change everything to inches:
2.75 ft = 33 in
1.5 ft = 18 in
Volume of tank = lwh = (33)(18)(7) = 4158 in³
The tank is 40% full, so only 60% is need to fill it. To find 60%, multiply 4158 by 0.6 = 2494.8 in³
Now find out how much 2494.8 in³ is in gallons:
231 in³ = 1 gallon
1 in³ = 1/231 gallons
2494.8 = (1/231)(2494.8) gallons = 10.8 gallons
Answer:
.34
Step-by-step explanation:
34% = 34/100 = .34
All percents are out of 100