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Can someone help me with this question please!!!!!

Can someone help me with this question please!!!!!-example-1
User OddBeck
by
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1 Answer

20 votes
20 votes

Solution:

We know that:

  • Interior angles of a triangle sum up to 180°.

  • 3a + 7u + 9 = 180\°

This means that:


  • (7u + 9) + (2a - 3) + 32 = 3a + 7u + 9

Let's simplify the equation to find a.

Step-by step calculations:

Open the brackets:


  • (7u + 9) + (2a - 3) + 32 = 3a + 7u + 9

  • 7u + 9 + 2a - 3 + 32 = 3a + 7u + 9

Cancel same terms on both sides:


  • 7u + 9 + 2a - 3 + 32 = 3a + 7u + 9

  • 2a - 3 + 32 = 3a

Simplify the LHS:


  • 2a + 29 = 3a

Subtract 2a both sides:


  • 2a - 2a + 29 = 3a - 2a
  • =>
    29 = 3a - 2a

Simplify the RHS and change the sides:

  • =>
    \bold{a = 29}

Let's substitute the value of a in 3a + 7u + 9 = 180° to find u.


  • 3a + 7u + 9 = 180\°
  • =>
    3(29) + 7u + 9 = 180\°

Simplify the LHS:

  • =>
    87 + 9 + 7u = 180
  • =>
    96 + 7u = 180

Subtract 96 both sides:

  • =>
    96 - 96 + 7u = 180 - 96
  • =>
    7u = 84

Divide 7 both sides:

  • =>
    (7u)/(7) = (84)/(7)
  • =>
    \bold{u = 12}

User Kadee
by
3.5k points