Answer: (30+40)+(3+4)
Step-by-step explanation:
Split the tens digits and the ones digits
If the backpack (b) contains only textbooks (t) and notebooks (n), the total weight of the backpack is:
b+t+n
but notebooks are 4 pounds, so actually:
b+t+4
also, the backpack weights 2 pounds, so the total weight is:
2+t+4 =t+6
now, "Seventy percent of
<span>
the total weight is textbooks. ", this means that
t=70%(t+6) - this equation can be used to determine the weight of the textbooks!
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28% means 28/100 which can be divided by 4/4 - the answer is 7/25
Answer:
x = -2, y = 7
Step-by-step explanation:
Since it's a system of equations, we know that the they use the same variables. To use substitution to solve a system of equation, we must take one equation and solve it for a variable, then you plug the solution into that variable for the other equation:
-2x + y = 11
y = 2x + 11
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4x + 4y = 20
4x + 4(2x + 11) = 20
4x + 8x + 44 = 20
12x + 44 = 20
12x = -24
x = -2
Then we can plug "x" into the first equation:
-2x + y = 11
-2(-2) + y = 11
4 + y = 11
y = 7
Answer:
hola CTMStep-by-step explanation: