Twelve added to a number equals 18 find the number

Identify the type of observational study described. a statistical analyst obtains data about ankle injuries by examining a hospital's records from the past 3 years. cross-sectional retrospective prospective

It is given that the quadratic equation hx²-3x+k=0, where h and k are constants, has roots [tex] \beta \: and \: 2 \beta [/tex]express h in terms of k

Emily is entering a bicycle race for charity. her mother pledges $0.90 for every 0.75 mile she bikes. if emily bikes 18 miles, how much will her mother donate?