Answer:
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Step-by-step explanation:
Let the missing number be 'x'
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Distribute x through the parentheses
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Swap the sides of the equation
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Add the numbers
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Collect like terms
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Divide both sides of the equation by 8
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Calculate
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Hope I helped!
Best regards!
Answer:
No it's not compulsory.
Step-by-step explanation:
If the ratio of sides are given then that can also help you find angle. Not only that if the relationship between the perpendicular and base are given then you can find angle
E.g.
if the ratios of the sides is 5:4:3 then you can find the angle
The green cone is ~410.5. the blue one is ~25.13