20 points if anwsered correctly

challenge after a heavy rain, a river reached the edge of its banks. any more rain and there would be a flood. after a few hours, the river went down one fifth inch
. then another rainstorm hit and dropped one fourth inch
of rain. the river rises by startfraction 1 over 20 endfraction
of the amount of rain that falls. use this expression negative one fifth plus startstartfraction one fourth overover startfraction 20 over 1 endfraction endendfraction
to find how the new water level compares to the riverbank. did the new rain cause a flood?
negative one fifth plus startstartfraction one fourth overover startfraction 20 over 1 endfraction endendfraction
equals
nothing

Intersecting secant-tangent theorem states that if a tangent segment and a secant segment are drawn to a circle from an exterior point, then the square of the measure of the tangent segment is equal to the product of the measures of the secant segment and its external secant segment.so to break it down: 1. pq acts as the tangent and ps as the secant with an intersection at p.sr = 21rp = 3x + 3pq = 4x + 4following to equation: tangent squared = the two segments multiplied by each otherso (4x + 4) ^ 2 = (3x + 3) • (21) simplifies to 16x^2 - 31x - 47 = 0 or (16x - 47)(x + 1) x = -1 or x = 47/162. pq acts as the tangent and ps as the secant with an intersection at p (again! )sr = 16rp = xpq = 15(15) ^ 2 = 16 • x225 = 16xx = 225/163. the interesting chords are proportional to each other so a ratio is possible to set up: ap dp 10 3 + x = = —— = pc pb 8 xcross multiple to get 10x = (3 + x)(8)x = 12

Understanding what? lol