How many protons are in an element with an atomic number of 8 and a mass number of 18?
2 answers:
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The value of x is 81
Step-by-step explanation:
The sum of the interior angles of any quadrilateral is 360°
- The measure of ∠1 is 40% of the sum of the angle measures of the quadrilateral
- The measure of ∠2 is 12.5% of the sum of the angle measures of the quadrilateral
- The measure of ∠3 is 25% of the sum of the angle measures of the quadrilateral
- We need to find the value of x
∵ The figure have 4 sides
∴ The figure is a quadrilateral
∵ The sum of the measures of the interior angles of a
quadrilateral is 360°
- Add the four angles and equate the sum by 360
∴ m∠1 + m∠2 + m∠3 + x = 360
∵ m∠1 = 40% of the sum of the angle measures of the quadrilateral
∴ m∠1 = 40% × 360 = × 360 = 144°
∵ m∠2 = 12.5% of the sum of the angle measures of the quadrilateral
∴ m∠2 = 12.5% × 360 = × 360 = 45°
∵ m∠3 = 25% of the sum of the angle measures of the quadrilateral
∴ m∠3 = 25% × 360 = × 360 = 90°
- Substitute these values in the equation above
∴ 144 + 45 + 90 + x = 360
- Add the like terms in the left hand side
∴ 279 + x = 360
- Subtract 279 from both sides
∴ x = 81°
The value of x is 81
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Answer:
266
Step-by-step explanation:
if a 45 minute workout is 1000 calories, at the same rate, a 12 minute workout would be 266 calories and 2 thirds. x 1000 = 266