Answer:
D=-4<0, the equation has no real solutions, it has two imaginary solutions.
Step-by-step explanation:
The quadratic equation
has coefficients
a=1,
b=4,
c=5.
The discriminant D is the expression

Hence,

Since the discriminant is negative, the equation has no real solutions, it has two imaginary solutions.
Answer:
a.) 
b.) 
c.) $
Step-by-step explanation:
a.) If she earns $7 'per' hour, this multiplication. After a week, we need to see how many hours she worked to earn $91, so this goes behind the equal sign. Let <em>h</em> be the unknown number of hours:

Solve for h. Divide both sides by 7:

Sylvia worked 13 hours at a rate of $7 an hour.
b.) She can work at most 15 hours a week. At 'most' can also mean less than or equal to. Let <em>h</em> be hours:

Sylvia can work less than or equal to 15 hours per week.
c.) If Sylvia can work 15 hours, plug in this value for <em>h</em> into an equation when she earns $7 per hour. Let the product of the hours and money equal <em>t</em> for total:

The most money Sylvia can earn in a week is $105.
<em>Finito.</em>
I believe this is a copy of an angle
DE = AB, EF = BC and AC = DF, hence triangle ABC is congruent to triangle DEF.
<h3>
Congruent shape</h3>
Two shapes are said to be congruent if they have the same shape, all their corresponding angles and sides are congruent to one another.
Given that DE = AB and BC = EF.
In right triangle DEF, using Pythagoras:
DF² = DE² + EF²
Also, In right triangle ABC, using Pythagoras:
AC² = AB² + BC²
But DE = AB and EF = BC, hence:
AC² = DE² + EF²
AC² = DF²
Taking square root of both sides, hence:
AC = DF
Since DE = AB, EF = BC and AC = DF, hence triangle ABC is congruent to triangle DEF.
Find out more on Congruent shape at: brainly.com/question/11329400