Answer:
x=40
Step-by-step explanation:
x=4(x+10)÷5
x=(4x+40)÷5
5x=4x+40
x=40
<span>y=(4/9)x-2
This is in slope intercept form (y=mx+b), where m is the slope.
A perpendicular line will have the opposite reciprocal of the slope.
So if the slope here is 4/9, then the perpendicular line's slope will be -9/4.
Now that you have the slope (-9/4) and a point (4, 3), you can use the point-slope formula to find the equation.
y - y</span>₁ = m(x - x₁)
y - 3 = (-9/4)(x - 4)
y - 3 = (-9/4)x + 9
y = (-9/4)x + 12
So the answer will be:
C. <span>y= -(9/4)x+12</span>
It is asking you to find the sum of k^2 - 1 from k=1 to k=4. Since that is only 4 numbers, calculating the sum by hand wouldn’t be that bad.
(1^2 - 1) + (2^2 - 1) + (3^2 - 1) + (4^2 - 1) = 26
The easier way to find the sum is to use a few simple formulas.
When we have a term that is just a constant c, the formula is c*n.
When we have a variable k, the formula is k*n*(n+1)/2.
When we have a squared variable, the formula is k*n*(n+1)*(2n+1)/6.
In this case, we have a squared variable k^2 and a constant of -1.
So plug in n=4 to the formulas:
4*5*9/6 - 1*4 = 26
The answer is 26
115% of the price is 270,25
115*x/100=270,25
x=270,25*100/115
x=235 $ is the price
270,25-235= 35,25 $ is the tax
