Question

3s+2t=-4-6s-10t=-7Value of s

Answer 1

s = -3

Explanation :

Using method of substitution by expressing one equation to only one variable.

Equation 1 : 3s + 2t = -4

Equation 2 : -6s - 10t = -7

Express equation 1 as t in terms of s :

`\begin{gathered} 3s+2t=-4 \\ 2t=-3s-4 \\ t=(-3s-4)/(2) \end{gathered}`

Substitute t to the equation 2 :

`\begin{gathered} -6s-10t=-7 \\ -6s-10((-3s-4)/(2))=-7 \\ -6s-5(-3s-4)=-7 \\ -6s+15s+20=-7 \\ 9s=-7-20 \\ 9s=-27 \\ s=-(27)/(9)=-3 \end{gathered}`

The answer is s = -3