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
let's firstly, convert the mixed fraction to improper fraction, and then subtract.
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Answer:
the answer is 309 r 15
Step-by-step explanation:
309 × 27 is 8343 and your left with 15
Answer:
178 ERASERS
Step-by-step explanation:
YOU NEED TO START BACKWARDS. HE BOUGHT 76 ERASERS AND HE HAS 193, SO WHATEVER HE HAD AT THE END OF TUESDAY+76 IS HOW MUCH HE HAS ON WEDNESDAY. 193-76=117. ON TUESDAY, HE STARTED WITH ERASERS AT END OF TUESDAY+39 ERASERS. 117+39=156. ON MONDAY, HE STARTED WITH END OF MONDAY+22 ERASERS. 156+22=178