DEF is a right angle ?

False

Step-by-step explanation:

Since we want to test if it is a right triangle, we can use Pythagorean Theorem

a^2+b^2=c^2

where a and b are the legs, and c is the hypotenuse.

In the given triangle, 23 and 26 are the legs, since they are shorter sides.  42 is the hypotenuse, since it is the longest side.

Therefore, a is 23, b is 26 and c is 42. Substitute these values into the equation

23^2+26^2=42^2

Evaluate the exponents

529+676=1764

Add 529 and 676

1205=1764

This statement is not true, 1205 is not equal to 1764. Therefore this is not a right triangle.

step-by-step explanation:

first, eliminate the parenthesis:

3

x

+

2

−

4

x

second, group like terms:

3

x

−

4

x

+

2

third, combine like terms:

(

3

−

4

)

x

+

2

→

−

1

x

+

2

→

−

x

+

2