How do you solve a simultaneous equation if the letter is the subject? e.g.
p = a + 5
164 = 8a + 9p
Thanks! :o)
2006-09-13 06:29:52 · 10 answers · asked by pixie.wings 1 in Science & Mathematics ➔ Mathematics
substitute p into the equation below.
2006-09-13 06:34:37 · answer #1 · answered by Truth speaker 2 · 0⤊ 0⤋
p = a + 5
164 = 8a + 9p
Substitute p = a + 5 into the bottom equation
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164 = 8a + 9p
164 = 8a + 9(a + 5)
164 = 8a + 9a + 45
The distributive property on the Right side
164 = 17a + 45
Collecting like terms
164 - 45 = 17a + 45 - 45
Subtracting - 45 from both sides of the equation
119 = 17a
119/17 = 17a/17
Dividing both sides of the equation by 17
7 = a
Insert the a value into the equation
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Solving for p
P = a + 5
p = 7 + 5
p = 12
Insert the p value into the equation
164 = 8a + 9p
164 = 8(7) + 9(12)
164 = 56 +108
164 = 164
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The answer is:
a = 7
p = 12
2006-09-13 14:45:39 · answer #2 · answered by SAMUEL D 7 · 0⤊ 0⤋
Substitute p = a + 5 in the second equation.
This will give you
164 = 8a + 9(a + 5)
which then you can simplify and solve for a.
Once you get the value of a, plug it back in either equation to get p.
2006-09-13 13:35:19 · answer #3 · answered by nb2020 2 · 1⤊ 0⤋
p = a + 5
164 = 8a + 9p
164=8a + 9(a+5)
164=8a +9a +45
119=17a
a=7
p=7+5=12
check work:
8(7) +9(12)=164
2006-09-13 14:58:00 · answer #4 · answered by when's my next vacation??? 4 · 0⤊ 0⤋
If both statements are correct, then 164 = 8a +9(a+5)
164 = 8a+9a+45
164 = 17a+45
119 =17a
a=7 and p=7+5
2006-09-13 13:49:10 · answer #5 · answered by davidosterberg1 6 · 0⤊ 0⤋
p = a + 5
164 = 8a + 9p
164 = 8a + 9(a + 5)
164 = 8a + 9a + 45
164 = 17a + 45
17a = 119
a = 7
p = 7 + 5 = 12
ANS :
a = 7
p = 12
2006-09-13 14:19:54 · answer #6 · answered by Sherman81 6 · 1⤊ 0⤋
substitute the value of p in second equation.. so that the equation becomes
164= 8a + 9(a+5)
now simplify the equation as 164= 17a+45
a=7
and p=12
2006-09-13 13:44:22 · answer #7 · answered by anandu 1 · 0⤊ 0⤋
p=164-8a/9 substitute this in equation 1
a=164-81/9 X 5
a=83-45/9
a=38/9
p=38/9+5
p=83/9
2006-09-13 13:36:55 · answer #8 · answered by Sai♥Pranav 3 · 0⤊ 0⤋
This is a really good one. They have already told you the value of p - it's (a+5)!
So in the second equation you put (a+5) instead of (p), and work it out from there!!!!!!
Good luck with your HW.
Hey pixie - can't you ask your Math. teacher these kind of questions? He/she is being paid to teach you, you know!
2006-09-13 13:42:26 · answer #9 · answered by Rose 5 · 0⤊ 0⤋
Can't help, these drove me to distraction at school, I could never see the point. Is there one?
2006-09-13 15:15:26 · answer #10 · answered by bo nidle 4 · 0⤊ 0⤋