4a+3a-4 = 10 4a+3a = 10+4 7a = 14 a = 2
4a - 5 = 7a - 7 -5 = 3a - 7 2 = 3a a = 3/2
It's a linear equation in ' a '.When you see one of these, it often happens that curiosity overtakes you, and you begin to wonder about the numerical value of ' a ' that makes the equation true. Let's find out:3a - 7a + 12 = 323a - 7a = 20-4a = 20a = 20 / (-4) = -5The equation is true if ( a = -5 ).
4a-2=7a-6 4=3a a=4/3
2a - 4y = 3a - 8a - 5y 7a = -ya = -(y/7)
4a+3a-4 = 10 4a+3a = 10+4 7a = 14 a = 2
4a - 5 = 7a - 7 -5 = 3a - 7 2 = 3a a = 3/2
-7a + 3a = -4a
a + 3a - 2 + 3a. Add the a + 3a + 3a = 7a. You can't combine the -2 & 7a so the solution is: 7a - 2.
It's a linear equation in ' a '.When you see one of these, it often happens that curiosity overtakes you, and you begin to wonder about the numerical value of ' a ' that makes the equation true. Let's find out:3a - 7a + 12 = 323a - 7a = 20-4a = 20a = 20 / (-4) = -5The equation is true if ( a = -5 ).
7a-17 = 4a+1 7a-4a = 1+17 3a = 18 a = 6
4a-2=7a-6 4=3a a=4/3
3a+5b+7a=
Clearly, there are some signs missing. So let's try the four possibilities for the second terms: 1. + and + 3a + 4b = 7a + 4b Subtract 4b from each side: 3a = 7a Subtract 3a from each side: 0 = 4a Answer : a = 0, b indeterminate (ie can have any vaue). 2. + and - 3a + 4b = 7a - 4b Subtract 4b from each side: 3a = 7a - 8b Subtract 7a from each side: -4a = -8b or 4a = 8b Answer: a = 2b 3. - and - 3a - 4b = 7a - 4b Add 4b to each side: 3a = 7a Subtract 3a from each side: 0 = 4a Answer : a = 0, b indeterminate (ie can have any vaue). 4. - and + 3a - 4b = 7a + 4b Add 4b to each side: 3a = 7a + 8b Subtract 7a from each side: -4a = 8b or 4a = -8b Answer: a = -2b Can't do better than that with the information available.
7a=2(-10)........................................answer is 20/7
2a - 4y = 3a - 8a - 5y 7a = -ya = -(y/7)
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