Y-8=-1/2x + (-2)
+8 +8
y=-1/2x +6
I just used a 2 step equation for it. I first used Distributive Property. Then Subtracted 8 from each side
Answer:
7 1/2 cups
Step-by-step explanation:
20 gallons is ten times 2 gallons.
Ten times the amount of water will require ten times the disinfectant (we assume).
... 10 × 3/4 cup = 30/4 cups = 7 1/2 cups
Answer:
238 mg
Step-by-step explanation:
340 x 0.30 = 102
340 - 102 = 238
Answer:
base length = 19 cm , height = 12 cm
Step-by-step explanation:
Area formula : A = (1/2)*b*h
b = h + 7 cm
A = 114 sq. cm
114 = (1/2) * (h + 7) *h
228 = hh + 7h
hh + 7h - 228 = 0
h = -7/2 + root( 49 - 4*(-228)) /2
h = -7/2 + 31/2
h = 24/2 = 12 cm
base = 12 cm + 7 cm = 19 cm
T=-1
sinA=sin(π/2-3A), A=2nπ+π/2-3A, 4A=2nπ+π/2, A=nπ/2+π/8 where n is an integer.
Also, π-A=2nπ+π/2-3A, 2A=2nπ-π/2, A=nπ-π/4.
The hard way:
cos3A=cos(2A+A)=cos(2A)cosA-sin(2A)sinA.
Let s=sinA and c=cosA, then s²+c²=1.
cos3A=(2c²-1)c-2c(1-c²)=c(4c²-3).
s=c(4c²-3) is the original equation.
Let t=tanA=s/c, then c²=1/(1+t²).
t=4c²-3=4/(1+t²)-3=(4-3-3t²)/(1+t²)=(1-3t²)/(1+t²).
So t+t³=1-3t², t³+3t²+t-1=0=(t+1)(t²+2t-1).
So t=-1 is a solution.
t²+2t-1=0 is a solution, t²+2t+1-1-1=0=(t+1)²-2, so t=-1+√2 and t=-1-√2 are solutions.
Therefore tanA=-1, -1+√2, -1-√2 are the three solutions from which:
A=-π/4, π/8, -3π/8 radians and these values +2πn where n is an integer.
Replacing π by 180° converts the solutions to degrees.
