У = 2х +7
y = x+8
using substitution

(1, 9)

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Equality Properties

Step-by-step explanation:

Step 1: Define Systems

y = 2x + 7

y = x + 8

Step 2: Solve for x

Substitution

Step 3: Solve for y

x = 1

y = 9

Step-by-step explanation:

y = 2x + 7 (I)

y = x + 8 (II)

Substitute y = 2x + 7 in equation (I)

    2x + 7 = x + 8           {Subtract 'x' from both sides}

2x + 7 - x = 8                 {Combine like terms}

      x + 7 = 8                  {Subtract 7 from both sides}

           x  = 8 -7

x = 1

Substitute x = 1 in equation (I)

y = 2*1 + 7

 = 2 + 7

y = 9

table 3 represents a direct variation function. : )