simplify these expression and find their values if x=3,p=-1,q=-2
10-3p-4+6q
Answers
Answered by
0
Step-by-step explanation:
If 3p - 2q = 10 and pq = -1, then find the value of 9p^2 + 4q^2
Solution -
3p - 2q \: = 103p−2q=10
{(3p - 2q)}^{2} = {10}^{2} (3p−2q)
2
=10
2
As we know, (a-b)^2 = a^2 + b^2 - 2ab
{(3p)}^{2} \: + {(2q)}^{2} + 2 \times 3p \times 2q \: = (3p)
2
+(2q)
2
+2×3p×2q=
{9p }^{2} + {4q}^{2} - 12pq9p
2
+4q
2
−12pq
As we know, pq = -1
{9p}^{2} + {4q}^{2} - 12 \times ( - 1)9p
2
+4q
2
−12×(−1)
{9p}^{2} + {4q}^{2} + 12 \: = 1009p
2
+4q
2
+12=100
{9p}^{2} + {4q}^{2} = 100 - 129p
2
+4q
2
=100−12
{9p}^{2} + {4q}^{2} = 889p
2
+4q
2
=88
Answer = 9p^2 +4q^2 = 88
Hope it helps u
Answered by
1
Answer:
10-(3× -1)-4+(6× -2)
=10-(-3)-4+(-12)
=10+3-4-12
=13-16
=-3
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