The third choice, 4x²+18x+0.25=0, is correct.
The frame will have the same thickness on both sides of the mirror. Therefore we add 5+x+x to get the total length, and we have 4+x+x to get the total width.
The area is found by multiplying the total width and total length:
A=(5+x+x)(4+x+x)
A=(5+2x)(4+2x)
Multiplying the binomials, we have:
A=5*4+5*2x+2x*4+2x*2x
A=20+10x+8x+4x²
A=20+18x+4x²
We know that the area is 19.75:
19.75=20+18x+4x²
We need quadratics set equal to 0, so subtract 19.75 from each side:
19.75-19.75 = 20+18x+4x²-19.75
0=0.25+18x+4x²
In standard form, it will be:
4x²+18x+0.25=0
Answer:
70
Step-by-step explanation:
The answer is 70 steps, because you walked 30 steps from the front to the store then you walk to the left of the store, you now can add these together to make 70 steps altogethor! how this helps!
Answer:
45 ways
Step-by-step explanation:
We are given;
there are 3 different math courses, 3 different science courses, and 5 different history courses.
Thus;
Number ways to take math course = 3
The number of ways to take science course = 3
The number of ways to take history course = 5
Now, if a student must take one of each course, the different ways it can be done is;
possible ways = 3 x 3 x 5 = 45 ways.
Thus, number of different ways in which a student must take one of each subject is 45 ways.
Answer:
a > b > c
Step-by-step explanation:
The longest side is the one that sees the angle with the biggest measure
The angles are shown in the image, the third angle is 75 degrees (because the sum of interior angle is equal to 180)
So the list of the sides in descending order is as follows :
a > b > c (a sees angle measure 75, b sees angle measure 70, and c sees angle measure 35)