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Given that angleA and angleB are complem...

Given that `angleA` and `angleB` are complementary angles. If `angleA=angleB+20^(@)`, then find `angleA` and `angleB`

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To solve the problem, we need to find the measures of angles A and B given that they are complementary angles and that angle A is 20 degrees more than angle B. ### Step-by-Step Solution: 1. **Understanding Complementary Angles**: Since angle A and angle B are complementary, we know that: \[ \text{angle A} + \text{angle B} = 90^\circ \] 2. **Setting Up the Equation**: We are also given that: \[ \text{angle A} = \text{angle B} + 20^\circ \] We can substitute this expression for angle A into the complementary angle equation. 3. **Substituting in the Equation**: Replace angle A in the first equation: \[ (\text{angle B} + 20^\circ) + \text{angle B} = 90^\circ \] 4. **Combining Like Terms**: Combine the terms: \[ 2 \cdot \text{angle B} + 20^\circ = 90^\circ \] 5. **Isolating angle B**: Subtract 20 degrees from both sides: \[ 2 \cdot \text{angle B} = 90^\circ - 20^\circ \] \[ 2 \cdot \text{angle B} = 70^\circ \] 6. **Dividing to Find angle B**: Divide both sides by 2: \[ \text{angle B} = \frac{70^\circ}{2} = 35^\circ \] 7. **Finding angle A**: Now that we have angle B, we can find angle A using the relation: \[ \text{angle A} = \text{angle B} + 20^\circ = 35^\circ + 20^\circ = 55^\circ \] 8. **Final Answers**: Therefore, the measures of the angles are: \[ \text{angle A} = 55^\circ \quad \text{and} \quad \text{angle B} = 35^\circ \] ### Summary of the Solution: - Angle A = 55 degrees - Angle B = 35 degrees
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NAVNEET PUBLICATION - MAHARASHTRA BOARD-LINE AND ANGLES-Skill Testing Exercise
  1. Given that angleA and angleB are supplementary angles. If angleA:angle...

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  2. angleA and angleB are complementary angles. If angleA=x+20^(@) and ang...

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  3. Given that angleA and angleB are complementary angles. If angleA=angle...

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  4. Given that angleX and angleY are supplementary angles. If angleX=5 ang...

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  5. angleP and angleQ are supplementary angles. If angleP=angleQ-40^(@), ...

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  6. In the following figure, l II m and t is their transversal. If angleXP...

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  7. In the following l II m and t is their transversal. If angleAXY=65^(@)...

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  8. In the following figure, t is the transversal of l and m. If angleAPQ=...

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  9. Ray AX is the bisector of angleBAC and ray AY is the bisector of angle...

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  10. Ray EX is the bisector of angleDEF and ray EY is the bisector of angle...

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  11. angleX and angleY are supplementary angles. If angleX:angleY=25:11, th...

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  12. If angleA and angleB are supplementary angles. If 4angleA=5angleB, the...

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  13. In DeltaABC,angleA:angleB:angleC=3:4:5. Find the measure of each angle...

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  14. In DeltaABC,angleA=(angleB+angleC)/(3) and angleB:angleC=2:1. Find the...

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  15. Side BC of DeltaABC is extended on both the sides so that exterior ang...

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  16. The side BC of DeltaABC is product to N. bisector of angle meets BC at...

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  17. For the figure given below, prove that / ADC = / A + / B + / C

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  18. In DeltaABC, bisectors of angleB and angleC interesct each other at po...

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  19. For the figure below, prove that / CBE + / ADF = / DAB + / DCB.

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  20. Prove that the sum of the angles of a quadrilateral is 360^(@) .

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