Respuesta :
Answer:
[tex] \boxed{ \bold{ \huge{ \boxed{ \sf{x = 8.4}}}}}[/tex]
Step-by-step explanation:
Given, y = 0.8
To find : value of x
[tex] \sf{4x + 8y = 40}[/tex]
plug the value of y
[tex] \longrightarrow{ \sf{4x + 8 \times 0.8 = 40}}[/tex]
Multiply the numbers: 8 and 0.8
[tex] \longrightarrow{ \sf{4x + 6.4 = 40}}[/tex]
Move 6.4 to right hand side and change it's sign
[tex] \longrightarrow{ \sf{4x = 40 - 6.4}}[/tex]
Subtract 6.4 from 40
[tex] \longrightarrow{ \sf{4x = 33.6}}[/tex]
Divide both sides by 4
[tex] \longrightarrow{ \sf{ \frac{4x}{4} = \frac{33.6}{4} }}[/tex]
Calculate
[tex] \longrightarrow{ \sf{x = 8.4}}[/tex]
Hope I helped!
Best regards ! :D