EFGH is a square. FG = MG and EK = JK. FGL, EMG, EKL and EHJ are straight lines. ∠FEL\angle FEL is twice of ∠FLE\angle FLE.

  1. (a)

    Find ∠FMG\angle FMG.

  2. (b)

    Find ∠GEL\angle GEL.

  3. (c)

    Find ∠KJE\angle KJE.

Work through it with AI →

It won't just hand you the answer — it asks where you're stuck.How the checker works

Worked solution

15(a)

1. Find the angle $\angle FGM$ using the property of the square's diagonal.

Since EFGHEFGH is a square and EGEG is its diagonal, it bisects the right angle at GG.
∠FGE=90∘2=45∘\angle FGE = \frac{90^\circ}{2} = 45^\circ
Since MM lies on EGEG, ∠FGM=45∘\angle FGM = 45^\circ.

2. Use the isosceles triangle $FMG$ to find $\angle FMG$.

Given FG=MGFG = MG, △FMG\triangle FMG is an isosceles triangle.
∠FMG=∠MFG\angle FMG = \angle MFG
∠FMG=180∘−45∘2=135∘2=67.5∘\angle FMG = \frac{180^\circ - 45^\circ}{2} = \frac{135^\circ}{2} = 67.5^\circ

Answer

67.5∘67.5^\circ

15(b)

1. Find $\angle FEL$ using the right-angled triangle $EFL$

Since EFGHEFGH is a square and FGLFGL is a straight line, ∠EFL=90∘\angle EFL = 90^\circ.
In △EFL\triangle EFL, ∠FEL+∠FLE=180∘−90∘=90∘\angle FEL + \angle FLE = 180^\circ - 90^\circ = 90^\circ.
Given ∠FEL=2∠FLE\angle FEL = 2\angle FLE, we have:
2∠FLE+∠FLE=90∘2\angle FLE + \angle FLE = 90^\circ
3∠FLE=90∘  ⟹  ∠FLE=30∘3\angle FLE = 90^\circ \implies \angle FLE = 30^\circ
∠FEL=2×30∘=60∘\angle FEL = 2 \times 30^\circ = 60^\circ

2. Find $\angle GEL$ by subtracting the diagonal angle

EGEG is the diagonal of square EFGHEFGH, so ∠FEG=45∘\angle FEG = 45^\circ.
∠GEL=∠FEL−∠FEG\angle GEL = \angle FEL - \angle FEG
∠GEL=60∘−45∘=15∘\angle GEL = 60^\circ - 45^\circ = 15^\circ

Answer

15∘15^\circ

15(c)

1. Find $\angle LEJ$ using the right angle of the square.

Since EFGHEFGH is a square and E,H,JE, H, J are collinear, ∠FEJ=90∘\angle FEJ = 90^\circ.
From earlier parts, ∠FEL=60∘\angle FEL = 60^\circ.
∠LEJ=∠FEJ−∠FEL=90∘−60∘=30∘\angle LEJ = \angle FEJ - \angle FEL = 90^\circ - 60^\circ = 30^\circ.

2. Use the isosceles triangle property to find $\angle KJE$.

In △EKJ\triangle EKJ, we are given EK=JKEK = JK, which means it is an isosceles triangle.
Therefore, the base angles are equal: ∠KJE=∠KEJ\angle KJE = \angle KEJ.
Since KK lies on ELEL, ∠KEJ=∠LEJ=30∘\angle KEJ = \angle LEJ = 30^\circ.
Thus, ∠KJE=30∘\angle KJE = 30^\circ.

Answer

30∘30^\circ

AI analysis — may contain mistakes.

Worked this one out on paper? Snap your steps and Gigle's AI math checker will circle the step where it went wrong.

More questions on this topic

  1. 1The figure below is made up of 2 squares, ABCD and DEFG. X is a point on GD and Y is a point on DE. BC = 7 cm, FE = 6 cm…
  2. 2The net drawn for the solid shown below is incorrect. Name the solid. Ans: (a)___ Shade a triangular face on the net tha…
  3. 3In the figure below, ABCD is a trapezium and AD = BC. Each of the statements is either true, false or not possible to te…
  4. 4In the figure, WXYZ is a trapezium and AXYB is a rhombus. XBC and XAZ are straight lines. WX // ZY, BC = BY, ∠XAB=82∘\angle XAB = 82^\circ…
  5. 5The figure below shows 12 identical squares. What is the least number of such squares that must be added to the figure s…