Respuesta :
Answer:
a = 15
Step-by-step explanation:
Given
3a + b = 54 ← substitute b = 9
3a + 9 = 54 ( subtract 9 from both sides )
3a = 45 ( divide both sides by 3 )
a = 15
The value of x in the equation 4x + 8y = 40 is 8.4. and the value of a in the equation 3a + b = 54 is 15.
What is a system of equations?
A system of equations is two or more equations that can be solved to get a unique solution. the power of the equation must be in one degree.
Given;
A) 4x + 8y = 40
Now substitute y = 0.8
4x + 8(0.8) = 40
4x = 40 - 6.4
x = 8.4
B) 3a + b = 54
Now substitute b = 9
3a + 9 = 54 ( subtract 9 from both sides )
3a = 45 ( divide both sides by 3 )
a = 15
Learn more about equations here;
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