Answer:
The first four.
Step-by-step explanation:
There are 3 main postulates. SSS, SAS, and AAS. This simply refers to how we prove a triangle congruent. With SSS, all 3 sides must be congruent (either proven or given). AAS is when you have 2 angles congruent with a side next to one of the angles. NOT IN BETWEEN (there's an image as to what I'm talking about below). Finally, SAS. This is when you have a set of angles congruent with sides on each side congruent as well (look at the first four as an example of this.
Any more specific questions, feel free to ask!
To solve for j, cross multiply:
4 x 45 = 18 x j
180 = 18j
Divide both sides by 18:
j = 10
The roots of an equation are simply the x-intercepts of the equation.
See below for the proof that
has at least two real roots
The equation is given as: 
There are several ways to show that an equation has real roots, one of these ways is by using graphs.
See attachment for the graph of 
Next, we count the x-intercepts of the graph (i.e. the points where the equation crosses the x-axis)
From the attached graph, we can see that
crosses the x-axis at approximately <em>-2000 and 2000 </em>between the domain -2500 and 2500
This means that
has at least two real roots
Read more about roots of an equation at:
brainly.com/question/12912962