Wow this question is very difficult,hold up
Theorem of cosine:
a²=b²+c²-2bc(cos α) ⇒cos α=-(a²-b²-c²) / 2bc
In this case:
a=15 cm
b=10 cm
c=5 cm
cos α=-(15²-10²-5²) / 2*10*5
cos α=-100 / 100
cos α=-1
A=arc cos -1=180º This is impossible, because:
A+B+C=180º; then B=C=0º This is impossible for make a triangle (B>0 and C>0 if we want to make a triangle).
Therefore: it is not possible can make a triangle with side lengths of 5 cm, 10 cm and 15 cm.
Answer:
x = 3
y = 1
Step-by-step explanation:
9x - y = 26 ---------------(I)
9x + y = 28 ---------------(II)
9x - y = 26
9x = 26 + y
Substitute 9x = 26 + y in equation (II)
26 + y + y = 28 {add like terms}
26 + 2y = 28 {subtract 26 from both sides}
2y = 28 - 26
2y = 2 {divide both sides by 2}
y = 2/2
y = 1
Substitute y =1 in equation (I)
9x - 1 = 26
9x = 26 + 1
9x = 27
x = 27/9
x = 3
x = 3
y = 1
There are six possible outcomes