Question

Please help me please

Answer 1

y = 3.4

Explanation:

Given 2 secants and a tangent drawn to the circle from an external point then

The square of the measure of the tangent is equal to the product of the external part of the secant to the entire secant.

Using the secant with measure y + 11, then

y(y + 11) = 7²

y² + 11y = 49 ( subtract 49 from both sides )

y² + 11y - 49 = 0 ← in standard form

with a = 1, b = 11 and c = - 49

Using the quadratic formula to solve for y

y = ( - 11 ±
`√(11^2-4(1)(-49))` ) / 2

= ( - 11 ±
`√(121+196)` ) / 2

= ( - 11 ±
`√(317)` ) / 2

y =
`(-11-√(317) )/(2)` or y =
`(-11+√(317) )/(2)`

y = - 14.4 or y = 3.4

However y > 0 ⇒ y = 3.4 ( nearest tenth )