a) $S^{EAG}=\genfrac{}{}{0ex}{}{1}{2}\times AG\times ED=\genfrac{}{}{0ex}{}{1}{2}\times 2\times 3=3\left(c{m}^2\right)$

$S^{PBC}=\genfrac{}{}{0ex}{}{1}{2}\times BC\times DC=\genfrac{}{}{0ex}{}{1}{2}\times 5\times 5=12,5\left(c{m}^2\right)$

b) Ta có:

$S^{EBC}=\genfrac{}{}{0ex}{}{1}{2}\times BC\times EC=\genfrac{}{}{0ex}{}{1}{2}\times 5\times 8=20\left(c{m}^2\right)$

$S^{PEC}=S^{ECB}-S^{PBC}=20-12,5=7,5\left(c{m}^2\right)$

Vậy nên:

$PD=\genfrac{}{}{0ex}{}{2\times S^{PEC}}{EC}=\genfrac{}{}{0ex}{}{2\times 7,5}{8}=1,875\left(cm\right)$

c) Ta thấy:

$\genfrac{}{}{0ex}{}{IM}{IP}=\genfrac{}{}{0ex}{}{S^{MIG}}{S^{IPG}}=\genfrac{}{}{0ex}{}{S^{MIE}}{S^{IPE}}$ nên $\genfrac{}{}{0ex}{}{IM}{IP}=\genfrac{}{}{0ex}{}{S^{MGE}}{S^{GPE}}=\genfrac{}{}{0ex}{}{\genfrac{}{}{0ex}{}{1}{2}\times MG\times 3}{\genfrac{}{}{0ex}{}{1}{2}\times GP\times 3}=\genfrac{}{}{0ex}{}{MG}{GP}$

Kéo dài AD cắt EF tại K.

Ta có $S^{AKM}=\genfrac{}{}{0ex}{}{1}{2}\times 3\times 2=3\left(c{m}^2\right)$

nên $S^{EKM}=S^{AKE}-S^{AKM}=\genfrac{}{}{0ex}{}{1}{2}\times 3\times 5-3=4,5\left(c{m}^2\right)$

Vậy $FM=\genfrac{}{}{0ex}{}{2\times S^{EKM}}{KE}=1,8\left(cm\right)$

Thế thì $MG=3-1,8=1,2\left(cm\right)$

Lại có $GP=3-1,875=1,125\left(cm\right)$

Vậy nên:

$\genfrac{}{}{0ex}{}{IM}{IP}=\genfrac{}{}{0ex}{}{MG}{GP}=\genfrac{}{}{0ex}{}{1,2}{1,125}=\genfrac{}{}{0ex}{}{16}{15}$.

1. What subjects does Nam have on Tuesday?

2. Does she have Maths today?

3. What can you do?

4. You have to do English today.

5. When do you have Science?

6. What subjects do you have today?

1.It's nine twenty.

2.There are two boys at the party.

3.Yes,he can

Yes,she can.

4.She's playing the piano.

She's dancing.

5.She want some grapes.

1.It's nine twenty.

2.There are two boys at the party.

3.Yes,he can

Yes,she can.

4.She's playing the piano.

She's dancing.

5.She want some grapes.

1.It's in November.

2.No,I can't,but I can draw pictures.

3.It's Sunday.

4.I study English st home.

5.I go to bed at nine thirty

1.It's in November.

2.No,I can't,but I can draw pictures.

3.It's Sunday.

4.I study English st home.

5.I go to bed at nine thirty.

1.It's ten twenty-five.

2.yes,she can.

3.Joey is from United States of America.

4.I listen to music on Sundays.

1.I want some jam.

2.It's in April.

3.It's Thursday.

4.I play chess on Monday.

1.It's ten twenty-five.

2.yes,she can.

3.Joey is from United States of America.

4.I listen to music on Sundays.

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