X=-1 and y=3
To solve this, because y is equal to 2x+5, you can substitute 2x+5 into the bottom equation for y.
You now have 3x - (2x + 5) =-6
This can be solved like a normal equation. Multiply each term in the parenthesis by -1.
3x - 2x - 5 = -6
Subtract 2x from 3x
x - 5 = -6
Add 5 to both sides
x=-1
Now you can solve for y by plugging -1 in for x in either equation. Im going to use the top one.
y= 2(-1)+5
y= -2+5
y=3
You can check your answer by plugging in the values for x and y into both equations and making sure both sides equal each other.
Step-by-step explanation:
I think what is meant in the triangle ABC we have the three angles.
the sum of all angles in a triangle is airways 180 degrees.
so,
180 = A + B + C
180 = 42 + B + C
now, we know also that
B = 5×C
so, we can use that above
180 = 42 + 5×C + C
138 = 6×C
C = 138/6 = 23 degrees
B = 5×C = 5×23 = 115 degrees
72% = 72/100
72/100=36/50=18/25
Answer:
Step-by-step explanation:
A question on a math quiz asks, "What is 175% of 72?" Petra calculates 12.6 as the answer. Is this a reasonable answer? Explain
A.) P(t) = P0exp(kt)
P(20/60) = 40 exp(20k/60)
80 = 40 exp(k/3)
exp(k/3) = 80/40 = 2
k/3 = ln(2)
k = 3ln(2)
b.) P(8) = 40(2)^24 = 40(16777216) = 671088640 cells
d.) Rate of change = exp(8k) = exp(8(3ln(2)) = exp(24ln(2)) = exp(16.6355) = 16777216 cells / hour
e.) P(t) = 40(2)^3t; t in hours
1,000,000 = 40(8)^t
25,000 = 8^t
ln(25,000) = t ln(8)
t = ln(25,000)/ln(8) = 4.87 hours