Answer:
a=2.48
c=9.52
Step-by-step explanation:
a+c=12
4a+7.5c=72.5 Given
a+c=12
-4a-7.5c=-72.5 multiply the equation by negative 1
-3a-6.5c=-60.5 simplify
-3a=-60.5+6.5c add 6.5c to both sides
a=-20.17+2.17c divide it by 3
now you would take that equation and plug it into an equation you already have since you have something to plug in for a, the easiest one to do is a+c=12
(-20.17+2.17c)+c=12 plug in the equation
-20.17+3.17c=12 simplify by solving for c
3.17c=30.17 add 20.17 to both sides
c=9.52 divide both sides by 3.17
now since you have found c, you can plug it in to you equation to solve for a now (use the ones from the second step). I am using the equation a+c=12.
a+9.52=12 plug in the variable and solve for a
a=2.48 subtract 9.52 to both sides
a=2.48
c=9.52
Answer:
21 N
Step-by-step explanation:
let mass be m and weight be w
Given w varies directly with m then the equation relating them is
w = km ← k is the constant of variation
To find k use the condition m = 7 , w = 49 , then
49 = 7k ( divide both sides by 7 )
7 = k
w = 7m ← equation of variation
When m = 3 , then
w = 7 × 3 = 21 N
Answer:
answer is ya mum
Step-by-step explanation:
10 times a number y
3 subtracted by A number x
12 times a number n
Answer: x = 7
Step-by-step explanation: