Answer:
Option A is correct, i.e. x = -3, x = 7.
Step-by-step explanation:
Given the equation is x² -4x -21 = 0.
We can compare it with general quadratic equation i.e. ax² +bx +c =0.
then a = 1, b = -4, c = -21.
We can use Quadratic formula as follows:-
x = ( -b ± √(b²-4ac) )/2a
x = ( +4 ± √(16-4*1*-21) )/2*1
x = ( +4 ± √(16+84) )/2
x = ( +4 ± √(100) )/2
x = ( +4 ± 10 )/2
x = (4+10)/2 or x = (4-10)/2
x = 14/2 or x = -6/2
x = 7 or x = -3
Hence, option A is correct, i.e. x = -3, x = 7.
Answer: 0.167
Step-by-step explanation:
This is an applied mathematics question
Resistors in parallel ⁾/R = ¹/₁₂₀ + ¹/₁₂₀ since the resistor is two 120
Therefore , resolve into fraction now yield
¹/R = 1 + 1
-------
120
= 2/120
= ¹/₆₀
Therefore, ¹/R = ¹/₆₀
Cross multiply to get R the resistance
R = 60
From formula, V = IR where I is the current
There fore making I the subject of the formula
I = V/R
= 10/60
= 0.166
= 0.167 A, A = ampere which is the unit of current.
Answer:
2x3 Top Planter - 6
2x6 Side of Planter - 12
Full Sqaure Feet - 72
Side Note:
Correct me if I am wrong.
I haven't done fifth/sixth grade math in a long time
