15x²+16x+4 =0 (ax² +bx +c=0)
Δ = b²-4ac =256 - 4×15×4 =16
x1 = (-b+√Δ) / 2a = (-16+√16) / 30 =( -16+4) / 30 = -12/30 = - 2/5
x2 = (-b -√Δ) / 2a = (-16 -√16) / 30 = (-16 -4) /30 = -20/30 = -2/3
For b it's 39 because you multiply 5 and 7 giving you 35 then add 4 Wich equals 39. I might be incorrect. check it out.
Answer:
Price went up, $24.64/year for 28 years
Step-by-step explanation:
Change Year = 28
Change Price = 690
Average rate = 690/28 = 24.64
Answer:
7 : 8
Step-by-step explanation:
150 adults complete a survey. 80 are women. Thus the ratio of number of men to number of women . Therefore the number of men to number of women be 7 : 8
