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If (5a+3b=35) and ( a/b = 2/5 ), what is the value of (a)?

A. ( 14/5 )
B. ( 7/2 )
C. (5)
D. (7)
E. (9)

User Ajaxx
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1 Answer

7 votes

Final answer:

To solve for the value of 'a', we use substitution from the given ratio a/b = 2/5 into the equation 5a + 3b = 35. Upon solving, we find that b = 7. Substituting b back into a's equation, we get a = 14/5, which is not in the presented options, so the answer is 'None of the above'.

Step-by-step explanation:

To find the value of a we have two equations:

  • 5a + 3b = 35 (Equation 1)
  • a/b = 2/5 (Equation 2)

From Equation 2, we can express a in terms of b: a = (2/5)b.

Substitute the expression for a from Equation 2 into Equation 1:

5((2/5)b) + 3b = 35

Simplify and solve for b:

2b + 3b = 35

5b = 35

b = 7

Now substitute b into the expression for a:

a = (2/5)(7)

a = 14/5 or a = 2.8, which is not in the provided options, so the answer is d. None of the above.

User Mdgrech
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