
Raphael K. answered 09/16/21
Expert in test taking strategies and placing high test scores
a first number plus twice the second number is 10 twice the first number plus the second totals 23 find the numbers? What is the smaller of the two numbers
First # = X
Second # = Y
X + 2Y = 10
2X + Y = 23
We can use substitution or elimination:
Substitution:
solve for x in the first equation:
X = 10 - 2Y
substitute for X in the 2nd equation:
2(10 - 2Y) + Y = 23
solve for y:
20 -4Y + Y = 23
20 - 3Y = 23
-3Y = 3
Y = -1
Sub Y=-1 in either equation to solve for X:
X = 10 - 2(-1)
X = 10 + 2
X = 12
Answer: The larger of the 2 numbers is 12, the smaller is -1.