## How to Measure an Angle Without a Protractor

Connect the two rays to form a triangle; the slope is the steepness of the diagonal line, or hypotenuse, of your triangle; type the value for slope into your scientific calculator; it will give you the degrees of the angle. Measure the obtuse angle with a ruler. Extend the bottom ray of the angle in a straight line.

In your scientific calculator, enter your slope value and then press the inverse tan button (tan-1). The value displayed is the number of degrees in the acute angle. A flat line is a straight line with 180 degrees; subtracting degrees from 180 will give you the degrees of your obtuse angle. Divide the length of the vertical line by the length of the horizontal line to get the angle’s slope.

## What can I use if I don’t have a protractor?

If you don’t have a protractor, you can use the basic geometric principles of triangles to determine the size of an angle, but you’ll need a scientific calculator to solve the equations; most smartphones have one, but you can also download a free app or access a free calculator online.

## How do you construct a 45 degree angle without a protractor?

Follow the steps outlined below.

- Draw a line segment BC of any length.
- With B as the center, draw a semicircle that bisects BC at point P.
- From P, draw three arcs that divide the semicircle into three equal parts, each with a 60o angle.
- Mark the points x and y where the arcs bisect the semicircle.

## What angle is 45?

What is a 45-Degree Angle? A 45-degree angle is half of a 90-degree angle formed between two rays. It is an acute angle and two angles measuring 45 degrees from a right angle or a 90-degree angle.

## What is a 40 angle?

Angles are classified based on their degree measures as follows: Acute Angle: An acute angle is defined as an angle with a magnitude greater than 0u00b0 but less than 90u00b0. Angles with magnitudes of 30u00b0, 40u00b0, and 60u00b0 are all acute angles.

## How do you construct a 90 degree angle?

With a protractor and a ruler, how do you make a 90-degree angle?

- Draw a line segment and label it as XY.
- Place the protractor’s midpoint or center on point X.
- Starting at 0u00b0 in the protractor, move counter-clockwise and mark a point at 90u00b0 as Z.
- Join the points Z and X.

## What does a 90 angle look like?

Angle DAB is a 90-degree angle that always corresponds to a quarter turn. Rectangle and square are the basic geometric shapes with all four angles measured as 90 degrees. When two lines intersect and the angle between them is 90 degrees, the lines are said to be perpendicular.

## Which angle is 60 degree?

An acute angle is one that measures more than 0u00b0 but less than 90u00b0; for example, angles measuring 30u00b0, 40u00b0, and 60u00b0 are all acute angles, so a 60-degree angle is an acute angle.

## How do you make a homemade protractor?

Create a 60o angle by folding a triangle with one edge from the upper left corner to the bottom center of the paper, and a 120o angle by folding the same triangle from the right side. Mark these angles on your protractor.

## What is a 100 degree angle called?

u2013 Obtuse Angle An obtuse angle is a type of angle with a degree measurement greater than 90 degrees but less than 180 degrees, such as 100 degrees, 120 degrees, 140 degrees, 160 degrees, 170 degrees, and so on.