Answer:
45
Step-by-step explanation:
A number consists of 2 digits whose sum is 9 => x + y = 9
If the order of the numbers is inverted, the result is equal to the given number plus 9 units => (10*y + x) + 9 = (10*x + y)
Thus:
x + y = 9 => multiply by -9 => 9*y + 9*x = 81
10*y + x + 9 = 10*x + y => 9*y - 9*x = -9
We are left then that:
9*y + 9*x = 81 (1)
9*y - 9*x = -9 (2)
we add both equations
18y = 72
y = 72/18 = 4
replacing
x + y = 9
x + 4 = 9
x = 5
Therefore the number is (10y + x) => (10 * 4 + 5) => 45
Answer:
256
Step-by-step explanation:
3200 x 0.08 = 256
Answer:
x3 + x2 - 1 = ( x 2 + 1) ( x + 1)
Step-by-step explanation:
<h3>
Answer:</h3>
y = 8/9x + 80/9
<h3>
Step-by-step explanation:</h3>
<u>We are given;</u>
- Equation of a line as 8x -9y -2 = 0
- Coordinates (-1,8)
We are required to determine the equation of a line parallel to the given line and passing through a point (-1,8)
<h3>Step 1: Determine the Gradient of the given line </h3>
- When an equation is written in the form y = mx + c, m is the gradient.
- Therefore; we could write the equation 8x -9y -2 = 0 in the form of y= mx + c
9y = 8x -2
y = 8/9x - 2/9
Therefore, the slope, m = 8/9
<h3>Step 2: Determine the equation of the line</h3>
- We need to know that parallel lines have the same gradient
- Therefore, the slope of the line in question is 8/9
- It passes through a point (-1, 8)
We can therefore, determine the equation;
Taking another point, (x,y)

9(y-8) = 8(x+1)
9y - 72 = 8x + 8
9y = 8x + 8 +72
9y = 8x + 80
y = 8/9x + 80/9
Therefore, the equation of the line is y = 8/9x + 80/9
Looks like ti 1.75 in. Hope this helps and let me know if it does or im woong