We'll use Cramer's rule for 2 equations:
ax + by = e
cx + dy = f
5x -3y = 18 a=5 b=-3 e=18
2x + 7y = -1 c=2 d=7 f=-1
denominator determinant (dn) = (a * d) - (c * b) = 5 * 7 - (2 * -3) = 41
x = [(e * d) - (f * b)] / dn
[18 * 7 - (-1 * -3)] / 41 =
123 / 41 = 3
y = [(a * f) - (c * e)] / dn
= (5 * -1) -(2 * 18) / 41 =
-41 / 41 = -1
Source:
1728.com/cramer.htm
Answer:
4 and 12
Step-by-step explanation:
a = young
b = old
b = 3a, a+b =2a+8 => a = 4, b = 12
Answer: rectangles are congruent if both of them have the opposite sides are equal
Step-by-step explanation: rectangles are congruent if both of them have the opposite sides are equal. Two squares are congruent if both of them have the same edges.
Answer:
33 is the right answer
Step-by-step explanation:
May this help you
Answer:
35cm
Step-by-step explanation:
Given data
Length= 21cm
Width= 28cm
Diagonal= ???
Applying Pythagoras theorem
D^2= L^2+W^2
D^2= 21^2+28^2
D^2= 441+784
D^2= 1225
D= √1225
D= 35cm
Hence the diagonal is 35cm