Consider an ac circuit consisting of a power supply and a resistor. if the current in the circuit at time t is i, sin wt, then the
power delivered to the resistor is 1, rsinº wt, where r is the resistance. express the power in terms of cos 2wt.
c. p=1,r+1,ʻr cos2wt
a p=*r+* 1, r cos 2wt
b. p=1,38-rocos 2wt
d.
p=1/r-10r cos 2wt

Ithink the answer is d.

Ok here we go ..there are plenty of ways to solve such math problems but we will go for the smartest and easiest ..5x+2y=7  -2x+6y=9we rearrange them into the following ..by multiplying the 1st equation by 2 it becomes 10x + 4y = 14we rearrange it and so it becomes 10x = 14 - 4yas for the second equation we multiply it by 5 and rearrange it so it becomes as to the following ..-10x + 30y = 45rearranging so 10x = 30y -45now 10x equals both 14 - 4y and 30y -45so   14 - 4y = 30y -4531 = 26yy= 31/26 = 1.19 or around 1.2so by now we can calculate x easily as  -2x+6y=9so 2x = 6y -9 = 6 * 31/26 - 9 = -1.84  then x = - 0.92 or around -0.9best luck!

1. use commutative property to reorder the terms.2x+81=0.2. move the constant to right side by adding its opposite on both sides. 2x+81-81=0-81.2x=(-81).3. divide the equation on both sides.2x ÷ 2 = 81 ÷ 2.x = -81/2. your answer is -81/2. if you need to simplify it into a decimal, it’s -40.5.