9514 1404 393
Answer:
(b) √65
Step-by-step explanation:
The modulus of a complex number is the root of the sum of the squares of the real and imaginary parts.
|1 -8i| = √(1² +(-8)²) = √(1+64) = √65
Answer:
2/3
Step-by-step explanation:
rise over run is 2 over 3, and it is positive because the y increases as the x increases!
Answer: a) about 450
Step-by-step explanation:
50 multiplied by 9 is 450 and its asking for an approximate so it would be anything near 450
Answer:
x=3
Explanation:
Let's write an equation for the area of this figure.
This figure can be divided into 2 rectangles, a vertical and horizontal rectangle.
Area of rectangle= length× breadth
Area of vertical rectangle= 6x
Length of horizontal rectangle= (7 -x) cm
Area of horizontal rectangle= x(7-x)
Since total area= 30 cm^2,
6x+ x(7-x)= 30
6x +7x -x^2= 30 (expand)
-x^2 +13x-30= 0 (bring all terms to one side)
x^2 -13x +30= 0 (divide by -1)
(x -10)(x -3)= 0 (factorise)
x -10= 0 or x -3= 0
x= 10 or x= 3
(reject)
We reject x=10 since from the diagram, x cm is less than 6cm.
Answer: y= -1/1x - 1
Okay, to find the equation you must find the y-intercept and the slope.
To find the y-intercept, you must find (0,y). This is the point on the y-axis where x is 0. So, where along the y-axis is there a point? There is a point at (0,-1). Therefore, your y-intercept is -1.
To find the slope, you must do rise/run. Go to a point on the line, such as (0,-1). You must go up (or down) until you get lined up with next point on the line. You go up one time. Then, you must go right (or left) to get to the exact point. In this case, the point would be (-1,0). You go left one time.
If you go down or left when doing rise/run, the number would be negative. Since you went left, that number would be negative.
So, our slope would be 1/-1, which can also be written as -1/1.
Now, write the equation. There is always an x next to the slope. y= -1/1x
Then, put the y-intercept next to it. If it is positive, use a +. If it is negative, use a -. It is negative.
Therefore, the answer is y= -1/1x -1.
