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If 3a + 2b = 7 and 2a + 2b = 9 , what is the value of

User Nohus
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1 Answer

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Hey there :)

We have two equations:
3a + 2b = 7
2a + 2b = 9

We need to solve simultaneously to find the values of a and b

eq.1 3a + 2b = 7
eq.2 ( 2a + 2b = 9 ) x -1 ) multiply by -1 to cancel 2b

3a + 2b = 7
- 2a - 2b = -9 ( Add both together )
-------------------
a = - 2

Substitute the value you found for a in a in order to find b

3( - 2 ) + 2b = 7 2( - 2 ) + 2b = 9
- 6 + 2b = 7 OR - 4 + 2b = 9
2b = 13 2b = 13
b =
(13)/(2) b =
(13)/(2)


User Taylor Lafrinere
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