Step-by-step explanation:
They are Alternate angles so they need to be equal to each other meaning you can right them like this;
[tex]4x + 2 = 86[/tex]
So to work out x you just have to separate x;
[tex]4x = 86 - 2 \\ 4x = 84 \\ x = \frac{84}{4} [/tex]
So
[tex]x = 21[/tex]
