Find the horizontal and vertical intercepts, estimate to the nearest tenth?

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Answer 1 · 2018-06-10T20:32:59

Visual #ul("estimates")#

#y_("intercept") = 2.5 = 2 5/10#
#x_("intercept")=1.6 =1 6/10#

#1.5< x_("intercept") < 2 color(white)("ddd")->color(white)("ddd")# I choose #1.6 =1 6/10#

#y_("intercept") = 2.5 = 2 5/10#

Note that the question stipulates that we must use tengths

Answer 2 · 2018-06-11T23:33:58

Calculating the intercepts and rounding to the closest tenth gives #(0,2.5),(1.7,0)#

I'm going to approach this question by not visually estimating but instead calculating and then rounding, if needed, to the nearest tenth.

There are two points that we can use with a high level of certainty: #(-1,4),(1,1)#

We can find the slope that results from connecting these two points:

#m=(y_2-y_1)/(x_2-x_1)=(1-4)/(1-(-1))=(-3)/(2)=-3/2#

And then we can use the point slope formula to find the equation of the line:

#(y-y_1)=m(x-x_1)#

#(y-4)=-3/2(x-(-1))#

#(y-4)=-3/2(x+1)#

I'll change this into the slope intercept form to better look at the intercepts:

#y=-3/2x-3/2+4#

#y=-3/2x+5/2#

When #x=0, y=5/2=2.5#

When #y=0#, we get:

#0=-3/2x+5/2#

#3/2x=5/2#

#3x=5=>x=5/3~~1.7#