The sum of 3 numbers is 20 .If we multiple the 3rd number by 2 and first number to the result we get 23.By adding 2nd and 3rd numbers to 3 times the first number we get 46 .Find the numbers by using cramer's rule.
Answers
X+Y+Z=20
2X+Y-Z=23
3X+Y+Z=46 ADD THE SECOND & THIRD EQUATIONS.
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5X+2Y=69
ADD THE FIRST & SECOND EQUATIONS.
X+Y+Z=20
2X+Y-Z=23
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3X+2Y=43 NOW ADD THIS EQUATION TO THE PREVIOUS SUM TIMES -1.
-5X-2Y=-69
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-2X=-26
X=-26/-2
X=13 ANS.
5*13+2Y=69
65+2Y=69
2Y=69-65
2Y=4
Y=4/2
Y=2 ANS.
13+2+Z=20
15+Z=20
Z=20-15
Z=5 ANS.
PROOF:
2*13+2-5=23
26-3=23
23=23
Step-by-step explanation:
X+Y+Z=20
2X+Y-Z=23
3X+Y+Z=46 ADD THE SECOND & THIRD EQUATIONS.
------------------
5X+2Y=69
ADD THE FIRST & SECOND EQUATIONS.
X+Y+Z=20
2X+Y-Z=23
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3X+2Y=43 NOW ADD THIS EQUATION TO THE PREVIOUS SUM TIMES -1.
-5X-2Y=-69
------------------
-2X=-26
X=-26/-2
X=13 ANS.
5*13+2Y=69
65+2Y=69
2Y=69-65
2Y=4
Y=4/2
Y=2 ANS.
13+2+Z=20
15+Z=20
Z=20-15
Z=5 ANS.
PROOF:
2*13+2-5=23
26-3=23
23=23