Question

What is the value of a if (2a+3)−(4a−8)=7?

Answer 1

Explanation:

2a + 3 - 4a + 8 = 7

-2a + 11 = 7

-2a = -4

a = 2

Answer 2

`\boxed{ \bold{ \huge{ \boxed{ \sf{a = 2}}}}}`

Explanation:

`\sf{(2a + 3) - (4a - 8) = 7}`

When there is a ( - ) in front of an expression in parentheses , change the sign of sign of each term in the expression

`\longrightarrow{ \sf{2a + 3 - 4a + 8 = 7}}`

Collect like terms

`\longrightarrow{ \sf{ - 2a + 3 + 8 = 7}}`

Add the numbers: 3 and 8

`\longrightarrow{ \sf{ - 2a + 11 = 7}}`

Move 11 to right hand side and change it's sign

`\longrightarrow{ \sf{ - 2a = 7 - 11}}`

Subtract 11 from 7

`\longrightarrow{ \sf{ - 2a = - 4}}`

Divide both sides by -2

`\longrightarrow{ \sf{ ( - 2a)/( - 2) = ( - 4)/( - 2) }}`

Calculate

`\longrightarrow{ \sf{a = 2}}`

Hope I helped!

Best regards! :D