I think it is Adjacent and Supplementary
Let the two numbers be x and y.
x + y = 86
+
x - y = 12
_________
2x + 0 = 98
__________
2x = 98
x = 98/2
x = 49
From x + y = 86
49 + y = 86
y = 86 - 49
y = 37
The numbers are 49 and 37.
Answer:
13x² - 4x
Step-by-step explanation:
3x + 4x² - 7x + 9x² ← collect like terms
= (4x² + 9x² ) + (3x - 7x)
= 13x² + (- 4x)
= 13x² - 4x
Answer:
19.44 hours, about 19 hours 26 minutes
Step-by-step explanation:
The exponential equation that describes your caffeine level can be written as ...
c(t) = 120·(1 -0.12)^t . . . . where t is in hours and c(t) is in mg
We want to find t for c(t) = 10, so ...
10 = 120(0.88^t)
10/120 = 0.88^t . . . . . . . divide by 120
log(1/12) = t·log(0.88) . . . take logarithms
t = log(1/12)/log(0.88) ≈ 19.4386
It will take about 19.44 hours, or 19 hours 26 minutes, for the caffeine level in your system to decrease to 10 mg.
