Core Connections Algebra 2, 2013
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Core Connections Algebra 2, 2013 View details
1. Section 2.1
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Exercise 35 Page 69

Practice makes perfect
a When we have a quadratic equation written in the form x^2+bx=0, we can solve this by factoring out the variable and then solving the resulting equation with the Zero Product Property.
y^2-6y=0
y(y-6)=0
lcy=0 & (I) y-6=0 & (II)
ly_1=0 y_2=6
b Notice that both sides of the equation contain a 7. Therefore, if we subtract 7 from both sides, we end up with an equivalent equation but without a constant. This can be solved by the Zero Product Property like we did in Part A.
n^2+5n+7=7
n^2+5n=0
n(n+5)=0
lcn=0 & (I) n+5=0 & (II)
ln_1=0 n_2=-5
c Like in Part B, we can solve this with the Zero Product Property if we first eliminate the constant from both sides.
2t^2-14t+3=3
2t^2-14t=0
2t(t-7)=0
t(t-7)=0
lct=0 & (I) t-7=0 & (II)
lt_1=0 t_2=7
d Like in Parts B and C, we can solve this equation with the Zero Product Property if we first eliminate the constant from both sides.
1/3x^2+3x-4=-4
1/3x^2+3x=0
x^2+9x=0
x(x+9)=0
lcx=0 & (I) x+9=0 & (II)
lx_1=0 x_2=-9
e Graphically, the solutions to a quadratic expression set equal to zero are its x-intercepts. Since all of the quadratic equations are without a constant, this means they intercept the y-axis at the origin, which also constitutes one of the x-intercepts.