Answer:
EF = 20 cm
Step-by-step explanation:
Here, we want to find the length of EF
To do this, we use the principle of similar triangles
The similar triangles we are considering here will be ;
FEA and FBD
when two triangles are similar, the ratio of their corresponding sides are equal
Let us calculate DC first
we can use Pythagoras’ theorem here and it is that the square of the hypotenuse equals the sum of the square of the two other sides
Using the triangle EDC
15^2 = 12^2 + DC^2
DC^2 = 225-144
DC^2 = 81
DC = 9
So the entire length of BD is 9 + 12 = 21 cm
Thus, we have it that;
Let EF be x
so DF = 15 + x
Hence;
BD/DF = AE/EF
21/15+x = 12/x
21x = 12(15 + x)
21x = 180 + 12x
21x-12x = 180
9x = 180
x = 180/9
x = 20 cm
EF = 20 cm
Answer:
y = -½x + 5
Step-by-step explanation:
Formula for slope intercept form is y = mx + b
Where m represents the slope and b represents the y intercept
.............................
Solving for m
...........................
m = (y2 - y1)/(x2-x1)
y2 = 4, y1 = 2
x2 = 2, x1 = 6
m = (4-2)/2-6)
m = 2/(-4)
m = -½
.......................
Solving for b
.........................
Using point F(6,2) as reference
y = 2, x = 6, m = -½
if y = mx + b
Substituting 2 for y and 6 for x in the above equation
2 = -½ * 6 + b
2 = -3 + b
2 + 3 = b
5 = b
b = 5
OR
Using Point G(2,4) as reference
y = 4, x = 2, m = -½
if y = mx + b
Substituting 4 for y and 2 for x in the above equation
4 = -½*2 + b
4 = - 1 + b
4+1 = b
5 = b
b = 5
.............................................
Finally, we have to write the equation in slope form
Using y = mx + b
where m = -½ and b =5 ................ (Calculated)
y = -½x + 5
The last one is correct answer
9x1=9
9-9(3n)
9-27n
Can’t be solved
