Question

How do i solve each proportion?

Answer 1

`19) (x + 4)/(3) = (4)/(10) \\ \\ x + 4 = (4)/(10) * 3 \\ \\ x = 1.2 - 4 = -2.8 \\ \\ x = -2.8 \\ \\ \\ 20) (4)/(n+8) = (10)/(8) \\ \\ 32 = 8n + 64 \\ \\ 8n = 32 -64 = -32 \\ \\ 8n = -32 \\ \\ n = -4`

Answer 2

You have to cross multiply (multiply the numerator of the first by the denominator of the second and the numerator of the second by the denominator of the first).

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[19]


`(x+4)/(3) = (4)/(10)`


`10x+40=12`


`10x = -28`


`x=-2.8`

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[21]


`(4)/(n+8) = (10)/(8)`


`32 = 8n + 64`


`8n = -32`


`n=-4`