Answer
let the first number be x
second number be y
5*(x)+y=-21---------->equation 1
2*(x)+y=-9------------->equation2
<h2>
eq1 * 2:</h2>
2(5x+y)=2*-21
10x+2y=-42
<h2>
eq2 * 5:</h2>
10x+5y=-45
10x+2y=-42
-(10x+5y=-45)
-----------------
0 - 3y=3
y=3/-3
<h2>
y=-1</h2><h3>
sub y=-1 in eq1;</h3><h3>
5x+y=-21</h3><h3>
5x+ -1=-21</h3><h3>
5x-1=-21</h3><h3>
5x=-21+1</h3><h3>
5x=20</h3><h3>
x=20/5</h3><h2>
x=4</h2><h2>
y=-1</h2>
To divide fractions, we do Keep, Change, Flip. Keep means that we keep the first fraction the same ( which is 8/1). Then for Change, we change the division sign to a multiplication sign. After that we Flip the second fraction itś reciprocal (or multiplicative inverse).
So your equation would be:
8/1 x 3/1 which equals 24
X=12.5
If the perimeter is 90
90=3x+3x+15
Combine like terms
90=6x+15
Subtracts 15 from both sides
75=6x
Divide by six to get x by itself
12.5=x
Does this help?
Answer:
B. Perimeter of a square and
C. Side length of a square
Step-by-step explanation:
if n= side length of square then
- Area of square is
- Perimeter of a square is 4×n
- diagonal length of a square is × n
Thus,
Perimeter of square can be expressed as
×diagonal length of a square
Side length of a square can be expressed as
×diagonal length of a square
but Area of square is
×n×diagonal length of a square
As a Result, Area of square is <em>also dependent of the value n</em>, wheras in other cases it is <em>a proportion of diagonal length of a square</em>
(3/7)-(1/14)=(6/14)-(1/14)=5/14
use LCD to get a like denominator, then just subtract