To find the value of [tex]\( b \)[/tex] in the equation [tex]\( b = 20 \sqrt{a} \)[/tex] given that [tex]\( a = 49 \)[/tex], we follow these steps:
1. Substitute the value of [tex]\( a \)[/tex] into the equation:
[tex]\[
b = 20 \sqrt{49}
\][/tex]
2. Calculate the square root of 49:
[tex]\[
\sqrt{49} = 7
\][/tex]
3. Multiply 20 by the square root of 49:
[tex]\[
b = 20 \times 7
\][/tex]
4. Perform the multiplication:
[tex]\[
b = 140
\][/tex]
Therefore, the value of [tex]\( b \)[/tex] is [tex]\( 140 \)[/tex].
