Y= 3x + 7, y = -4x + 10. solve by graphing method

x = 0.4, Y = 8.3

Step-by-step explanation:

Step 1. Create a table of values for each equation.

x     3x + 7  -4x + 10

-2         1          18

-1         4          14

0         7         10

1        10           6  

2       13           2

Step 2. Plot these points on one set of axes

They should look something like Fig.1 below.

Step 3. Draw straight lines through the points.

Your graph should like Fig. 2 below.

The point of intersection is the solution to the two equations.  

The point of intersection is not integral, so we must estimate its position.

It looks like the lines cross at x = 0.4, Y = 8.3.

Check:

   y = 3x+ 7                y = -4x + 10

8.3 = 3× 0.4 + 7     8.3 = -4 × 0.4 + 10

8.3 = 1.2 + 7           8.3 = -1.6 + 10

8.3 = 8.2                8.3 = 8.4

The results agree within ±0.1 unit, and that's the best we could estimate.