Question

if a+b =60 a-b =40 and a =22 find b

Answer 1

Hey mate your answer is
a+b=60, a=22
b=60-22
b=38
A-b= 40
-b= 40-22
b= -18
please mark me as Brainliest

Answer 2

Answer :

$\bf | \vec{b}| = 46$

Step-by-step explanation :

We have ;

$| \vec a+ \vec b| = 60 \\ \\ \sf{squaring \: both \: sides}.. \\ \\ (| \vec a+ \vec b| ) {}^{2} =( 60) {}^{2} \\ \\ | \vec a+ \vec b| {}^{2} =3 600 \\ \\ | \vec a| {}^{2} + | \vec b| {}^{2} + 2. | \vec a| . | \vec b| = 3600...(i) \\ \\ | \vec a - \vec b| = 40 \\ \\ \sf{squaring \: both \: sides}.. \\ \\ (| \vec a - \vec b| ) {}^{2} =( 40) {}^{2} \\ \\ | \vec a - \vec b| {}^{2} =1600 \\ \\ | \vec a| {}^{2} + | \vec b| {}^{2} - 2. | \vec a| . | \vec b| = 1600...(ii) \\ \\ \sf on \: adding \: (i) \: and \: (ii) \\ \\ | \vec a| {}^{2} + | \vec b| {}^{2} + 2. | \vec a| . | \vec b| + | \vec a| {}^{2} + | \vec b| {}^{2} - 2. | \vec a| . | \vec b| \\ = 3600 + 1600 \\ \\ 2( | \vec a| {}^{2} + | \vec b| {}^{2} ) = 5200 \\ \\ | \vec a| {}^{2} + | \vec b| {}^{2} = 2600 \\ \\ 22 {}^{2} + | \vec b| {}^{2} = 2600 \\ \\ | \vec b| {}^{2} = 2600 - 484 \\ \\ | \vec b| {}^{2} = 2116 \\ \\ \bf | \vec b| = 46$

Hence, $\bf | \vec b| = 46$