Step-by-step explanation:
explain step by step on photo, double check just in case
When you don't use or write the percent right.<span />
1 gallon cost $15
1 quarts cost $4
1 quarts = 1/4 gallon
15x for number of gallon cans
2 cans at $4 each = $8
15x + 8 = 53
Subtract 8 from both sides:
15x = 53-8
15x = 45
Divide both sides by 15:
x = 45/15
x = 3
She bought 3 gallon cans of paint
Plus she bought 2 quart cans, which is equal to a half gallon.
She bought a total of 3.5 gallons of paint.
I've answered your other question as well.
Step-by-step explanation:
Since the identity is true whether the angle x is measured in degrees, radians, gradians (indeed, anything else you care to concoct), I’ll omit the ‘degrees’ sign.
Using the binomial theorem, (a+b)3=a3+3a2b+3ab2+b3
⇒a3+b3=(a+b)3−3a2b−3ab2=(a+b)3−3(a+b)ab
Substituting a=sin2(x) and b=cos2(x), we have:
sin6(x)+cos6(x)=(sin2(x)+cos2(x))3−3(sin2(x)+cos2(x))sin2(x)cos2(x)
Using the trigonometric identity cos2(x)+sin2(x)=1, your expression simplifies to:
sin6(x)+cos6(x)=1−3sin2(x)cos2(x)
From the double angle formula for the sine function, sin(2x)=2sin(x)cos(x)⇒sin(x)cos(x)=0.5sin(2x)
Meaning the expression can be rewritten as:
sin6(x)+cos6(x)=1−0.75sin2(2x)=1−34sin2(2x)
