Question

NEED GEO HELP URGENT?

Answer 1

Secant and tangent theorem: Square of measure of tangent is equal to the product of length of whole secant and length of exterior secant segment, i.e.

`\text{ tangent }^2=\text{whole secant}\cdot \text{exterior secant}`.

The whole secant wuth exterior secant 4 cm is 4+x cm. Tangent is 7 cm. Using previous theorem, you can get that

`7^2=(4+x)\cdot 4`.

Solve this equation:

`49=16+4x,\\ 4x=49-16,\\ 4x=33,\\ x=8.25\approx 8.3` cm.

Answer: x=8.3 cm.