Question

A quadrilateral has three acute angles each measuring 70°. what is the measure of the fourth angle​

Answer 1

Answer:

Given :

$\sf{Three\: angles \:of \:the\: quadrilateral \:are\: {70}^{\circ}\:each}$

To find :

$\textsf{The fourth angle of the quadrilateral}$

Concept :

Let the fourth angle be x .

First see the measure of all the angles of the quadrilateral is 360° .

After that the equation will form like this -:

$\sf\boxed{x+{70}^{\circ}+{70}^{\circ}+{70}^{\circ}={360}^{\circ}}$

Solution :

$\sf\implies{x+{70}^{\circ}+{70}^{\circ}+{70}^{\circ}={360}^{\circ}}$

$\sf\implies{x+{140}^{\circ}+{70}^{\circ}={360}^{\circ}}$

$\sf\implies{x+{210}^{\circ}={360}^{\circ}}$

$\sf\implies{x={360}^{\circ}-{210}^{\circ}}$

$\sf\implies{x={150}^{\circ}}$

So , the fourth angle of the quadrilateral is 150° . And it is an obtuse angle .

Answer :

Fourth angle of the quadrilateral = 150° .

Answer 2

Answer:

3×70+x=360°

=>210+x=360°

=>x=360°-210°=150°

Hence fourth angle is 150°.