Let r be the decay rate (time in minutes) 17 = 20 e^(5r) 0.85 = e^(5r) ln 0.85 = 5r similarly, ln 0.5 = hr ... where h is the half-life, so dividing the 2 equations, ln 0.85 / ln 0.50 = 5r / hr = 5/h h = 5 ln 0.50 / ln 0.85 h = 21.3 min b) 1/20 = 0.05, so ln 0.85 = 5r ln 0.05 = tr t = 5 ln 0.05 / ln 0.85 t = 92.2 min
Answer:
42 = (3 +x)(4 +x)
Step-by-step explanation:
The only equation that has the existing dimensions <em>increased</em> by x is the first one.
Step-by-step explanation:
the line passes through (0,-2) and perpendicular to the graph of y=5x+7.
solution :
the slope = -1/5
the equation :
y+2 = -1/5 (x-0)
y = -1/5x - 2
Answer:
7 tenths
Step-by-step explanation:
3 tenths + 4 tenths = 3/10 + 4/10 = 0.3 + 0.4 = 0.7
= 7 tenths
